Uses Of Laser And Rapeseedoliveoil

Saturated Fat (% of total calories)

FIGURE 8-2 Relationship between blood total cholesterol concentrations and saturated fatty acid intake. Reprinted, with permission, from Clarke et al. (1997). Copyright 1997 by the British Medical Journal.

Density Ranges Lipoproteins
FIGURE 8-3 Calculated changes in serum low density lipoprotein cholesterol concentration in response to percent change in dietary saturated fatty acids. Three regression equations were used to establish the response curves. The range in saturated fatty acid intake was 2.2 to 33 percent of energy.

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 483

in energy from saturated fatty acids, serum LDL cholesterol concentration increases by 0.033 mmol/L (Mensink and Katan, 1992), 0.036 mmol/L (Clarke et al., 1997), or 0.045 mmol/L (Hegsted et al., 1993). Although all fats will increase serum high density lipoprotein (HDL) cholesterol concentration relative to carbohydrate, the increase attributable to saturated fats is greater than that observed for monounsaturated and polyunsaturated fatty acids. Serum HDL cholesterol concentration increases by 0.011 to 0.013 mmol/L for each 1 percent increase in saturated fat (Clarke et al., 1997; Hegsted et al., 1993; Mensink and Katan, 1992).

Similar to that observed for saturated fatty acid intake and LDL cholesterol concentration, there is a positive linear relationship between serum total and LDL cholesterol concentrations and risk of coronary heart disease (CHD) or mortality from CHD (Jousilahti et al., 1998; Neaton and Wentworth, 1992; Sorkin et al., 1992; Stamler et al., 1986; Weijenberg et al., 1996). Results from the Zutphen Elderly Study estimated that the relative risk of CHD mortality was 1.4 with a corresponding increase of 1 mmol/L of total serum cholesterol concentration (Weijenberg et al., 1996). It has been estimated that a 10 percent reduction in serum cholesterol concentration would reduce CHD mortality by 20 percent (Jousilahti et al., 1998).

A number of epidemiological studies have reported an association between saturated fatty acid intake and risk of CHD. The majority of these studies have reported a positive relationship between saturated fatty acid intake and risk of CHD and CHD mortality (Goldbourt et al., 1993; Hu et al., 1997, 1999a, 1999c; Keys et al., 1980; McGee et al., 1984). Ascherio and coworkers (1996) concluded that the association between saturated fatty acid intake and risk of CHD was not strong; however, saturated fat and the predicted effects on blood cholesterol concentrations did affect risk. No association between saturated fatty acid intake and coronary deaths was observed in the Zutphen Study or the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (Kromhout and de Lezenne Coulander, 1984; Pietinen et al., 1997).

Although all saturated fatty acids were originally considered to be associated with increased adverse health outcomes, including increased blood cholesterol concentrations, it later became apparent that saturated fatty acids differ in their metabolic effects (e.g., potency in raising blood cholesterol concentrations). In general, stearic acid has been shown to have a neutral effect on total and LDL cholesterol concentrations (Bonanome and Grundy, 1988; Denke, 1994; Hegsted et al., 1965; Keys et al., 1965; Yu et al., 1995; Zock and Katan, 1992). While palmitic, lauric, and myristic acids increase cholesterol concentrations (Mensink et al., 1994), stearic acid is more similar to oleic acid in its neutral effect (Kris-Etherton et al., 1993). Furthermore, a stearic acid-rich diet has been shown to improve

484 DIETARY REFERENCE INTAKES

thrombogenic and atherogenic risk factor profiles (Kelly et al., 2001). However, it is impractical at the current time to make recommendations for saturated fatty acids on the basis of individual fatty acids.

Mortality. A number of studies have demonstrated a positive association between serum cholesterol concentration and the incidence of mortality (Conti et al., 1983; Corti et al., 1997; Haheim et al., 1993; Klag et al., 1993; Martin et al., 1986). Some studies, however, have reported an increased risk of non-CHD mortality, especially cancer, with low serum cholesterol concentration, suggesting a "U" or 'J" shaped curve (Agner and Hansen, 1983; Frank et al., 1992; Kagan et al., 1981). The Poland and United States Collaborative Study on Cardiovascular Epidemiology showed an increased risk for cancer with low serum cholesterol concentrations in Poland, but not in the United States (Rywik et al., 1999). It was concluded that various nutritional and non-nutritional factors (obesity, smoking, alcohol use) were confounding factors, resulting in the differences observed between the two countries. As a specific example, body fat was shown to have a "U" shaped relation to mortality (Yao et al., 1991).

Obesity. A number of studies have attempted to ascertain the relationship between saturated fatty acid intake and body mass index, and these results are mixed. Saturated fatty acid intake was shown to be positively associated with body mass index or percent of body fat (Doucet et al., 1998; Gazzaniga and Burns, 1993; Larson et al., 1996; Ward et al., 1994). In contrast, no relationship was observed for saturated fatty acid intake and body weight (González et al., 2000; Ludwig et al., 1999; Miller et al., 1994).

Impaired Glucose Tolerance and Risk of Diabetes. Epidemiological studies have been conducted to ascertain the association between the intake of saturated fatty acids and the risk of diabetes. A number of these studies found no relationship (Colditz et al., 1992; Costa et al., 2000; Salmerón et al., 2001; Sevak et al., 1994; Virtanen et al., 2000). Several large epidemio-logical studies, however, showed increased risk of diabetes with increased intake of saturated fatty acids (Feskens et al., 1995; Hu et al., 2001; Marshall et al., 1997; Parker et al., 1993). The Normative Aging Study found that a diet high in saturated fatty acids was an independent predictor for both fasting and postprandial insulin concentration (Parker et al., 1993). A reduction in saturated fatty acid intake from 13.9 to 7.8 percent of energy was associated with an 18 percent decrease in fasting insulin and a 25 percent decrease in postprandial insulin concentrations.

Findings from short-term intervention studies tend to suggest a lack of adverse effect of saturated fatty acids on risk indicators for diabetes in

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 485

healthy individuals. Postprandial glucose and insulin concentrations were not significantly different in men who ingested three different levels of saturated fatty acids (Roche et al., 1998). Fasching and coworkers (1996) reported no difference in insulin secretion or sensitivity in men who consumed a 33 percent saturated, monounsaturated, or polyunsaturated fatty acid diet. There was no difference in postprandial glucose or insulin concentration when healthy adults were fed butter or olive oil (Thomsen et al., 1999). Louheranta and colleagues (1998) found no difference in glucose tolerance and insulin sensitivity in healthy women fed either a high oleic or stearic acid diet. In contrast, results of the KANWU study indicate that consumption of high levels (18 percent of energy) of saturated fats can significantly impair insulin sensitivity (Vessby et al., 2001).

Summary

Intakes above an identified UL indicate a potential risk of an adverse health effects. There is a positive linear trend between total saturated fatty acid intake and total and LDL cholesterol concentration and increased risk of CHD. A UL is not set for saturated fatty acids because any incremental increase in saturated fatty acid intake increases CHD risk. It is neither possible nor advisable to achieve 0 percent of energy from saturated fatty acids in typical whole-food diets. This is because all fat and oil sources are mixtures of fatty acids, and consuming 0 percent of energy would require extraordinary changes in patterns of dietary intake, such as the inclusion of fats and oils devoid of saturated fatty acids, which are presently unavailable. Such extraordinary adjustments may introduce undesirable effects (e.g., inadequate intakes of protein and certain micro-nutrients) and unknown and unquantifiable health risks. It is possible to consume a diet low in saturated fatty acids by following the dietary guidance provided in Chapter 11.

Cis-Monounsaturated Fatty Acids Hazard Identification

Cardiovascular Disease. Within the range of usual intake, there are no clearly established adverse effects of n-9 monounsaturated fatty acids in humans. There is some preliminary evidence that a meal providing 50 g of fat from olive oil reduced brachial artery flow-mediated vasodilation by 31 percent in 10 healthy, normolipidemic individuals versus canola oil or salmon (Vogel et al., 2000). In addition, there is evidence from nonhuman primates that a diet rich in n-9 monounsaturated fatty acids promotes

486 DIETARY REFERENCE INTAKES

atherosclerosis just as much as a diet containing isocaloric amounts of saturated or polyunsaturated fatty acids (Rudel et al., 1997). Dietary mono-unsaturated fatty acids induce atherogenesis due to greater hepatic lipid concentrations (i.e., triacylglycerol, free cholesterol, and cholesteryl ester), as well as the high degree of cholesteryl oleate enrichment in plasma cholesteryl esters. Overconsumption of energy related to a high n-9 mono-unsaturated fatty acid and high fat diet is another potential risk associated with excess consumption of monounsaturated fatty acids. n-9 Mono-unsaturated fatty acid intake may result in an increase in energy intake from saturated fatty acids due to the simultaneous occurrence of saturated and n-9 monounsaturated fatty acids in animal fats.

The n-7 monounsaturated fatty acid, palmitoleic acid, behaves like saturated fatty acids in raising LDL cholesterol concentration (Nestel et al., 1994). Watts and coworkers (1996) reported a positive correlation between palmitoleic acid and progression of CHD.

Cancer. While most epidemiological studies indicate that mono-unsaturated fatty acid intake is not associated with increased risk of most cancers (Holmes et al., 1999; Hursting et al., 1990; van Dam et al., 2000; van den Brandt et al., 1993), a few studies have observed a positive association. There is some epidemiological evidence for a positive association between oleic acid intake and breast cancer risk in women with no history of benign breast disease (Velie et al., 2000). In addition, one study reported that women with a family history of colorectal cancer who consumed a diet high in mono- and polyunsaturated fatty acids were at greater risk of colon cancer than women without a family history (Slattery et al., 1997). Giovannucci and coworkers (1993) reported a positive association between monounsaturated fatty acid intake and risk of advanced prostate cancer, while two studies observed increased risk of lung cancer (De Stefani et al., 1997; Veier0d et al., 1997).

Summary

Based on the lack of adequate data on adverse effects of mono-unsaturated fatty acids, a UL is not set.

n-6 Polyunsaturated Fatty Acids

A UL is not set for n-6 polyunsaturated fatty acids because of the lack of a defined intake level at which an adverse effect can occur (see Chapter 11). An AMDR for n-6 polyunsaturated fatty acids, however, is estimated based on adverse effects from consuming a diet low or high in n-6 polyunsaturated fatty acids (Chapter 11).

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 487

n-3 Polyunsaturated Fatty Acids

Because the longer-chain n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are biologically more potent than their precursor, a-linolenic acid, much of the work on the adverse effects of this group of fatty acids has been on DHA and EPA.

Hazard Identification

Immune Function. Numerous studies have shown suppression of various aspects of human immune function in vitro or ex vivo in peripheral blood mononuclear cells, or in isolated neutrophils or monocytes in individuals provided n-3 polyunsaturated fatty acids as a supplement or as an experimental diet compared with baseline values before the intervention (Table 8-8). The minimum dose observed for such an effect was 0.9 g/d of EPA and 0.6 g/d of DHA given as fish oil for 6 to 8 weeks to healthy adults (Cooper et al., 1993). The level of EPA that caused some type of immunosuppression ranged from 0.9 to 9.4 g/d when fed for 3 to 24 weeks. The level of DHA that caused immunosuppression ranged from 0.6 to 6.0 g/d (Table 8-8).

The data in single treatment studies comparing baseline versus post-supplementation immune function indicate that n-3 polyunsaturated fatty acids, especially EPA and DHA at levels 7 to 15 times greater than typical current U.S. intakes, diminish the potential of the immune system to attack pathogens (Kelley et al., 1998, 1999; Lee et al., 1985; Schmidt et al., 1989). This diminished ability, however, is also associated with suppression of inflammatory responses, suggesting benefits for individuals suffering from autoimmune diseases such as rheumatoid arthritis. It seems that the same doses of n-3 fatty acids that may be beneficial in chronic disease prevention are doses that are also immunosuppressive.

Several studies using a design of comparison across treatment groups (Blok et al., 1997; Kelley et al., 1998; M0lvig et al., 1991; Yaqoob et al., 2000), rather than comparison within individuals with a baseline, have shown a lack of several potential adverse effects of EPA and DHA supplementation on human immune cell functions. In one key study, 58 healthy men were given daily supplements of 0, 3, 6, or 9 g/d of a fish-oil supplement (EPA intake of 0, 0.81, 1.62, or 2.43 g/d and DHA intake of 0, 0.16, 0.33, or 0.49 g/d) for 1 year (Blok et al., 1997). Ex vivo endotoxin-stimulated production of interleukin (IL)-1ß, tumor necrosis factor (TNF)-a, or IL-1Ra (IL-1 receptor antagonist) did not differ among treatments up to 6 months after the fish-oil supplementation was stopped. These data support a lack of long-term adverse effect of fish-oil supplementation on cytokine activity.

TABLE 8-8 Effects

DIETARY REFERENCE INTAKES

of n-3 Fatty Acid Intake on Immune Function

Reference

Study Design n-3 Fatty Acid Dose (Daily)a

Endres et al., 1989

Schmidt et al., 1989

7 men 6 wk

9 men 6 wk

12 men 6 wk

Kelley et al., 1991

Meydani et al., 1991

10 men 56-d crossover

6 young women, 6 older women 12 wk

Basal diet

Flaxseed oil-supplemented diet (20 g 18:3n-3)

M0lvig et al., 1991

8 men

9 men

8 men 7 wk

Placebo oil

Fish oil (1 g EPA, 0.5 g DHA) Fish oil (2 g EPA, 1 g DHA)

Thompson et al., 1991

Virella et al., 1991

6 men, 6 women 4-wk crossover

4 men fed fish oil,

2 men fed olive oil 6 wk

MaxEPA (2.16 g EPA) 12 g olive oil

Yamashita et al., 1991

3 adults 1 d

3 g EPA, infused

Cooper et al., 1993

Endres et al., 1993

Meydani et al., 1993

Sperling et al., 1993

8 men and women 6-8 wk

9 men

6 wk

7 women, 3 men 24 wk after 6 wk on typical U.S. diet (baseline)

5 women and 3 men with rheumatoid arthritis

10 wk

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 489

Results b

Depressed neutrophil LTB4, 6-irans-LTB4, 5-HETE, and endothelial adherence, monocyte LTB4 and 5-HETE, neutrophil Chemotaxis

Depressed PBMC IL-1ß, IL-1a, TNF, PGE2, and neutrophil chemotaxis

Depressed neutrophil migration, monocyte cell density (marker of monocyte migration)

Depressed PBMC proliferation in response to T-cell mitogen but not to B-cell mitogen with flaxseed oil-supplemented diet

Depressed PBMC IL-1ß and IL-6 (greater in older women), TNF and IL-2 (older women only)

Depressed PBMC proliferation, IL-1ß in PBMCs and monocytes with n-3 fatty acids

PBMC secretion of IL-1ß, TNF-a, PGE2 or LTB4 not affected by n-3 fatty acids

Depressed neutrophil chemiluminescence (marker of neutrophil function) with MaxEPA diet Depressed PBMC IL-2

Depressed NK cell activity of PBMCs

Typhoid vaccine injection site less inflamed, postvaccination tachycardia inhibited, depressed blood IL-1 and IL-6 concentrations

Depressed PBMC IL-2 and proliferation

Depressed PBMC IL-1P, TNF, IL-6, PGE2, CD4+ lymphocytes, and lymphocyte proliferation, delayed-type hypersensitivity

Depressed neutrophil chemotaxis, inositol tris-phosphate formation, and LTB4, monocyte LTB4

490 DIETARY REFERENCE INTAKES

TABLE 8-8 Continued

Reference

Study Design

n-3 Fatty Acid Dose (Daily)a

Gallai et al., 1995

20 patients with relapsing/remitting multiple sclerosis and 15 controls 6 mo

Fish oil (3.06 g EPA, 1.86 g DHA)

4-wk diet + 4-wk diet with fish oil

Flaxseed oil-enriched diet and fish oil (EPA 1.62 g, DHA 1.08 g)

Sunflower oil diet and fish oil (EPA 1.62 g, DHA 1.08 g)

Hughes et al., 1996

3 men, 3 women 3 wk

EPA Forte (0.93 g EPA, 0.63 g DHA)

Blok et al., 1997

58 men 1 y

0, 3, 6, or 9 g fish oil (0, 0.81, 1.62, or 2.43 g EPA; 0, 0.16, 0.33, or 0.49 g DHA)

Kelley et al., 1998

DHA-enriched oil (6 g DHA)

Kelley et al., 1999

DHA-enriched oil (6 g DHA)

Yaqoob et al., 2000

5 men, 3 women

7 men, 1 woman

3 other groups of 8 fed other oils, but all comparable to placebo 12-wk parallel

Placebo oil (3:1 coconut and soybean oils) Fish oil (2.1 g EPA, 1.1 g DHA)

a EPA = eicosapentaenoic acid, DHA = docosahexaenoic acid.

b LTB4 = leukotriene B4, 5-HETE = 5-hydroxyeicosatetraenoic acid, PBMC = peripheral blood mononuclear cell, IL = interleukin, TNF = tumor necrosis factor, PGE2 = prosta-

In studies using multitreatment parallel designs, potential adverse effects of n-3 fatty acids on immune function that were observed include decreased expression of monocyte major histocompatibility complex antigens and cell surface adhesion proteins (Hughes et al., 1996), decreased peripheral blood mononuclear cell (PBMC) proliferation and IL-ip in

DIETARY FATS: TOTAL FAT AND FATTY ACIDS

Results b

Depressed PBMC IL-ip, TNF-a, IL-2 and IFN-y, PGE2, and LTB4, serum-soluble IL-2 receptors

Depressed PBMC TNF-a, IL-1P, TxB2, and PGE2 with flaxseed oil-enriched diet

Greater decreases in PBMC TNF-a, IL-1P, and TxB2 in both groups after fish-oil supplementation

Depressed monocyte surface proteins: HLA-DR, HLA-DP, HLA-DQ, ICAM-1, LFA-1

No effect on whole blood IL-1P, TNF-a, or IL-1 receptor antagonist

Decreased white blood cells

PBMC proliferation and delayed-type hypersensitivity not different between groups

Depressed PBMC IL-ip and TNF-a production, in vitro PBMC PGE2 and LTB secretion

No effect of fish oil on PBMC NK cell activity, proliferation, types of blood lymphocytes, IL-1 a, IL-ip, TNF-a, IL-2, IL-10, and IFN-y glandin E2, NK cell = natural killer cell, IFN-y = interferon-y TxB2 = thromboxane B2, HLA = human leukocytes antigen, ICAM = intercellular adhesion molecule, LFA = leukocyte function-associated antigen.

PBMCs and monocytes (M0lvig et al., 1991), decreased PBMC IL-2 (Virella et al., 1991), decreased but still clinically normal neutrophils (Kelley et al., 1998), and decreased tachycardia and inflammation after typhoid vaccine (Cooper et al., 1993).

492 DIETARY REFERENCE INTAKES

All of the single treatment studies comparing individuals fed n-3 poly-unsaturated fatty acids before and after supplementation showed immu-nosuppressive effects. Differences in study design (single treatment versus multitreatment parallel designs) seem to be quite significant in determining whether n-3 fatty acid supplementation exerts immunosuppression or not. There is no clear basis to prefer one type of study design to the other. For example, the difference in results between Caughey and colleagues (1996) (a baseline comparison study) and Blok and colleagues (1997) (a group comparison study) is not accounted for by greater variability in measurements by the latter group. The standard deviation for whole blood TNF-a was no more than 5 percent of the mean in the study by Blok and coworkers (1997), and the standard deviation for mononuclear cell TNF-a was 25 to 45 percent of the mean in the study by Caughey and coworkers (1996). In another study using intertreatment comparisons of control versus men given fish oil for 7 weeks, secretions of IL-1P and TNF-a were not suppressed by fish-oil feeding, but lysates of peripheral blood mono-nuclear cells from people given fish oil contained less IL-1P and TNF-a than did cells from controls (M0lvig et al., 1991). Therefore, the study by M0lvig and colleagues (1991) showed some concurrence with that of Blok and colleagues (1997) and Caughey and colleagues (1996).

Another alternative is to extrapolate from animal studies using model species that are known to have similar immune system components and responsiveness compared to humans. Detailed characterization of appropriateness of animal models for extrapolation to humans with respect to immunosuppression has not been done. A few animal studies have shown the effects of dietary n-3 fatty acids on response to infection (Chang et al., 1992; Fritsche et al., 1997). At this time, there are not sufficient data to support establishing an UL for EPA and DHA based on infection responsiveness.

Bleeding and Increased Risk of Hemorrhagic Stroke. One of a number of factors that has been suggested to link n-3 polyunsaturated fatty acid intake with reduced risk of CHD is reduced platelet aggregation, and therefore prolonged bleeding time. The platelet count can decline by as much as 35 percent; however, the count does not usually fall below the lower limit of normal (Goodnight et al., 1981). Although prolonged bleeding times have been shown to be beneficial in preventing heart disease, bleeding times can become prolonged enough to result in excessive bleeding and bruising. Intervention studies that have examined the effects of n-3 fatty acids on bleeding time are mixed. A number of short-term studies (4 to 11 weeks) have shown significant increased bleeding time with taking EPA/DHA supplements ranging from 2 to 15 g/d (Cobiac et al., 1991; De

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 493

Caterina et al., 1990; Levinson et al., 1990; Lorenz et al., 1983; Mortensen et al., 1983; Sanders et al., 1981; Schmidt et al., 1990, 1992; Smith et al., 1989; Thorngren and Gustafson, 1981; Wojenski et al., 1991; Zucker et al., 1988), whereas other studies using similar intake levels resulted in no difference (Blonk et al., 1990; Freese and Mutanen, 1997; Rogers et al., 1987). Analysis of these studies collectively indicated no dose-response for EPA and DHA intake and the percent increase in bleeding time. Schmidt and coworkers (1992) reported increased bleeding times when 3.1 g/d of EPA and DHA were given for 6 weeks and 9 months. None of the above studies reported excessive bleeding times, bleeding episodes, or bruising.

Dietary feeding studies that provided approximately 2 percent of energy as EPA and DHA from salmon did not result in increased bleeding time compared to a stabilization diet that contained only 0.3 percent of energy as EPA and DHA (Nelson et al., 1991). Excessive cutaneous bleeding time and reduced in vitro platelet aggregability have been reported in Greenland Eskimos (Dyerberg and Bang, 1979; Dyerberg et al., 1978) who ingest on average 6.5 g/d (3.8 percent of energy) of EPA and DHA derived mainly from seal (Bang et al., 1980). A tendency to bleed from the nose and urinary tract was observed among the Greenland Eskimos (Bang and Dyerberg, 1980). One study comparing perirenal adipose tissue fatty acid profiles with incidence of hemorrhagic stroke in human autopsy cases from Greenland showed that the amounts of EPA and DHA in the adipose tissue of 4 hemorrhagic stroke victims was greater than in 26 control cases with no cerebral pathology (Pedersen et al., 1999). Furthermore, ecological studies have suggested an increased risk of hemorrhagic stroke among Greenland Eskimos (Kristensen, 1983; Kromann and Green, 1980). A recent prospective study in the United States showed no association between intake of n-3 fatty acids and risk of hemorrhagic stroke (Iso et al., 2001). The median intake levels for the quintiles of n-3 polyunsaturated fat intake, however, ranged from only 0.077 to 0.481 g/d, which reflects the relatively low intake level of n-3 fatty acids in the Unites States.

Oxidative Damage. Long-chain polyunsaturated fatty acids, particularly DHA and EPA, are vulnerable to lipid peroxidation, resulting in oxidative damage of various tissues. Numerous feeding studies using laboratory animals have demonstrated increased lipid peroxidation and oxidative damage of erythrocytes, liver, and kidney membranes and bone marrow DNA with consumption of DHA (Ando et al., 1998; Song and Miyazawa, 2001; Umegaki et al., 2001; Yasuda et al., 1999). The oxidative damage was shown to be reduced or prevented with the coconsumption of vitamin E (Ando et al., 1998; Leibovitz et al., 1990; Yasuda et al., 1999).

494 DIETARY REFERENCE INTAKES

Summary

While there is evidence to suggest that high intakes of n-3 polyunsaturated fatty acids, particularly EPA and DHA, may impair immune response and result in excessively prolonged bleeding times, it is not possible to establish a UL. Studies on immune function were done in vitro and it is difficult, if not impossible, to know how well these artificial conditions simulate human immune cell response in vivo. Data on EPA and DHA intakes and bleeding times are mixed and a dose-response effect was not observed. Although excessively prolonged bleeding times and increased incidence of bleeding have been observed in Eskimos, whose diets are rich in EPA and DHA, information is lacking to conclude that EPA and DHA were the sole basis for these observations. At the 99th percentile of intake, the highest intakes of dietary EPA and DHA were 0.662 and 0.651 g/d, respectively, in men 71 years of age and older (Appendix Tables E-12 and E-14). This EPA + DHA intake (1.31 g/d) is much lower than that for Greenland Eskimos (6.5 g/d). EPA and DHA are available as dietary supplements, and until more information is available on the adverse effects of EPA and DHA, these supplements should be taken with caution.

Special Considerations

A few special populations have been reported to exhibit adverse effects from consuming n-3 polyunsaturated fatty acids. Despite the favorable effects of n-3 fatty acids on glucose homeostasis, caution has been suggested for the use of n-3 fatty acids in those individuals who already exhibit glucose intolerance or diabetic conditions (Glauber et al., 1988; Kasim et al., 1988) that require increased doses of hypoglycemic agents (Friday et al., 1989; Stacpoole et al., 1989; Zambon et al., 1992). Increased episodes of nose bleeds have been observed in individuals with familial hypercholes-terolemia during fish-oil supplementation (Clarke et al., 1990). Anticoagulants, such as aspirin, warfarin, and coumadin, will prolong bleeding times and the simultaneous ingestion of n-3 fatty acids by individuals may excessively prolong bleeding times (Thorngren and Gustafson, 1981). Therefore, the subpopulations described above should take supplements containing EPA and DHA with caution.

Trans Fatty Acids

Hazard Identification

Total and LDL Cholesterol Concentrations. Prior to 1980 there was generally little concern about the trend toward increased consumption of

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 495

hydrogenated fat in the U.S. diet, especially when the hydrogenated fats displaced fats relatively high in saturated fatty acids (Denke, 1995). During the early 1980s studies showed a hypercholesterolemic effect of trans fatty acids in rabbits (Kritchevsky, 1982; Ruttenberg et al., 1983). Renewed interest in the topic of hydrogenated fat in human diets, or more precisely trans fatty acid intake, started in the early 1990s. The availability of a methodology to distinguish the responses of individual lipoprotein classes to dietary modification expanded the depth to which the topic could be readdressed.

A report from the Netherlands suggested that a diet enriched with elaidic acid (a subfraction of 18:1 trans) compared to one enriched with oleic acid (18:1 cis) increased total and LDL cholesterol concentrations and decreased HDL cholesterol concentrations, hence resulting in a less favorable total cholesterol:HDL cholesterol ratio (Mensink and Katan, 1990). Consumption of a diet enriched with saturated fatty acids resulted in LDL cholesterol concentrations similar to those observed after individuals consumed the diet high in elaidic acid, but HDL cholesterol concentrations were similar to those observed after individuals consumed the diet high in oleic acid. A number of similar studies have been published since then and have reported that hydrogenated fat/trans fatty acid consumption increases LDL cholesterol concentrations (Aro et al., 1997; Judd et al., 1994, 1998; Louheranta et al., 1999; Müller et al., 1998; Sundram et al., 1997) (Tables 8-9, 8-10, and 8-11). Recent data have demonstrated a dose-dependent relationship between trans fatty acid intake and the LDL:HDL ratio and when combining a number of studies, the magnitude of this effect is greater for trans fatty acids compared with saturated fatty acids (Figure 8-4) (Ascherio et al., 1999).

Similar to the metabolic clinical trial data, studies in free-living individuals asked to substitute hydrogenated fat for other fat in their habitual diet resulted in higher concentrations of total and LDL cholesterol (Table 8-11) (Nestel et al., 1992b; Noakes and Clifton, 1998; Seppänen-Laakso et al., 1993).

No studies have been conducted to evaluate the effect of trans fatty acids that are present in meats and dairy products on LDL concentrations. The relative effect of trans fatty acids in meat and dairy products on LDL cholesterol concentration would be small compared to hydrogenated oils because of the lower levels that are present, and because any rise in concentration would most likely be due to the abundance of saturated fatty acids.

HDL Cholesterol Concentrations. The data related to the impact of hydrogenated fat/trans fatty acids compared with unhydrogenated oil/cis fatty acids on HDL cholesterol concentrations are less consistent than for LDL cholesterol concentrations (Tables 8-9, 8-10, and 8-11). As reported

496 DIETARY REFERENCE INTAKES

TABLE 8-9 Dietary Trans Fatty Acids (TFA) and Blood Lipid Concentration: Controlled Feeding Trials

Reference

Study Population

Dieta

Mensink and Katan, 1990; Mensink et al., 1992

79 men and women, avg 25-26 y

3-wk crossover, 40% fat 10% 18:1 10% SF 10% TFA

Zock and Katan, 1992

56 healthy men and women

3 wk crossover, 41% fat 18:2 18:0 TFA

Judd et al., 1994

58 men and women

6-wk crossover, 40% fat 18:1 SFA

moderate TFA high TFA

Aro et al., 1997

80 healthy men and women, 20-52 y

5-wk intervention, 33% fat 18:0 TFA

Sundram et al., 1997

27 men and women, 19-39 y

12:0 + 14:0 TFA

Louheranta et al., 1999

14 healthy women, avg 23 y

4-wk crossover, 37% fat 18:1 TFA

Judd et al., 2002

50 men

TFA/18:0 TFA

a SF = saturated fat, SFA = saturated fatty acids.

b LDL-C = low density lipoprotein cholesterol, HDL-C = high density lipoprotein cholesterol, Lp(a) = lipoprotein(a).

DIETARY FATS: TOTAL FAT AND FATTY ACIDS

Blood Lipid Concentrations b

2.67c 3.14d 3.04e

1.42c 1.42c 1.25d

32c 26d 45 e

2.83c 3.00d 3.07d

1.47c 1.41d 1.37d

2.89c 3.13d

1.42c 1.22d

270c 308d

1.25

2.95c 3.10d 3.32e 3.36e c,d,e Within each study, LDL-C, HDL-C, or Lp(a) concentrations that are significantly different between treatment groups have a different superscript.

498 DIETARY REFERENCE INTAKES

TABLE 8-10 Hydrogenated Fat Intake and Blood Lipid Concentrations: Controlled Feeding Trials

Population

Dieta

Lichtenstein

14 men and

32-d crossover, 30% fat

et al., 1993

women,

Baseline

44-78 y

Corn oil

Corn oil margarine

Almendingen

31 men,

3-wk crossover,

et al., 1995

21-46 y

33-36% fat

Butter

PHFO

PHSO

Judd et al.,

46 men and

5-wk crossover,

1998b

women,

34% fat

28-65 y

PUFA-M

Butter

TFA-M

Müller et al.,

16 healthy

14-d crossover,

1998

females,

31-32% fat

19-30 y

Vegetable oil

PHFO

Lichtenstein

36 men and

35-d crossover, 30% fat

et al., 1999

women,

Soybean oil

> 50 y

Semiliquid margarine

Butter

Soft margarine

Shortening

Stick margarine

a PHFO = partially hydrogenated fish oil, PHSO = partially hydrogenated soybean oil, PUFA-M = margarine containing polyunsaturated fatty acids, TFA-M = margarine containing trans fatty acids. b TFA = trans fatty acids.

for LDL cholesterol concentrations, the effect of hydrogenated fat/trans fatty acids on HDL cholesterol concentrations, if present, is likely to be dose-dependent (Judd et al., 1994). The preponderance of the data suggests that hydrogenated fat/trans fatty acids, relative to saturated fatty acids, result in lower HDL cholesterol concentrations (Ascherio et al., 1999; Zock and Mensink, 1996; Zock et al., 1995). Because of the potentially

DIETARY FATS: TOTAL FAT AND FATTY ACIDS

TFAb

Blood Lipid Concentrations^

3.96d 3.23e 3.49e

1.24d 1.14e 1.11e

140d 160d 130d

3.81d

3.94dJ

3.58e

1.05d 0.98e 1.05d

194d 234e 238e

3.21

3.44e

1.24d 1.27d 1.24d

197d 186e 202d

2.63d 2.87e

1.32d 1.28d

212d 225d

1.11d'e

1.11d'e

1.16e

1.11d,e

1.11d'e

1.01d

230 230 220 240 240 240

c LDL-C = low density lipoprotein cholesterol, HDL-C = high density lipoprotein cholesterol, Lp(a) = lipoprotein(a).

d,e,f Within each study, LDL-C, HDL-C, or Lp(a) concentrations that are significantly different between treatment groups have a different superscript.

differential effects of hydrogenated fat/ trans fatty acids on LDL and HDL cholesterol concentrations, concern has been raised regarding their effect on the total cholesterol or LDL cholesterol:HDL cholesterol ratio (Ascherio et al., 1999). However, with respect to dietary fat recommendations, the strategy to improve the total cholesterol or LDL cholesterol:HDL

DIETARY REFERENCE INTAKES

TABLE 8-11 Dietary Trans Fatty Acids (TFA), Hydrogenated Fat, and Blood Lipid Concentrations: Free-Living Trials

Reference

Study Population

Diet"

Nestel et al. 1992a

26 mildly hypercholesterolemic men, 27-57 y

4-wk crossover Control 1 Control 2 Blend 1 Blend 2

42% fat

Nestel et al. 1992b

27 mildly hypercholesterolemic men, 30-63 y

3-wk crossover fat Control 18:1 TFA 16:0

Seppänen-Laakso et al. 1993

57 men and women, middle-aged

12-wk crossover to 1 of 2

diets, 39-43% fat Margarine Rapeseed Olive oil

Wood et al., 1993a

38 healthy men, 30-60 y

Wood et al., 1993b

29 healthy men, 30-60 y

6-wk crossover, 38% fat Butter

Butter-sunflower Butter-olive Hard margarine Soft margarine

6-wk crossover, 37% fat

Butter

Crude palm

Margarine

Refined palm

Refined palm+sunflower

Sunflower oil

Chisholm et al., 1996

49 hypercholesterolemic men and women, avg 47 y

6-wk crossover fat Butter Margarine

DIETARY FATS: TOTAL FAT AND FATTY ACIDS

Blood Lipid Concentrationsc

235c 236c 296d 249e

Change from baseline

Change from baseline +0.05 -0.01 0.00

4.21c 3.82d

1.26c 1.24c

223c 249c

502 DIETARY REFERENCE INTAKES

TABLE 8-11 Continued

Reference

Study Population

Diet"

Noakes and

38 mildly hyperlipidemic

3-wk crossover, 2 groups,

Clifton,

men and women

31-35% fat

1998

Canola + TFA

TFA-free canola

Butter

PUFA + TFA

TFA-free PUFA

Butter

a PUFA = polyunsaturated fatty acids.

b LDL-C = low density lipoprotein cholesterol, HDL-C = high density lipoprotein cholesterol, Lp(a) = lipoprotein(a).

FIGURE 8-4 Change in the low density lipoprotein (LDL):high density lipoprotein (HDL) cholesterol concentration with increasing energy intake from saturated and trans fatty acids. Solid line represents the best-fit regression for trans fatty acids. Dotted line represents the best-fit regression for saturated fatty acids. Reprinted, with permission, from Ascherio et al. (1999). Copyright 1999 by the Massachusetts Medical Society.

Percentage of Energy from Fat

FIGURE 8-4 Change in the low density lipoprotein (LDL):high density lipoprotein (HDL) cholesterol concentration with increasing energy intake from saturated and trans fatty acids. Solid line represents the best-fit regression for trans fatty acids. Dotted line represents the best-fit regression for saturated fatty acids. Reprinted, with permission, from Ascherio et al. (1999). Copyright 1999 by the Massachusetts Medical Society.

DIETARY FATS: TOTAL FAT AND FATTY ACIDS

Blood Lipid Concentrations^

TFA (% of

LDL-C

HDL-C

Lp(a)

energy)

(mmol/L)

(mmol/L)

(units/L)

3.3

3.64c

1.19c

0

3.61c

1.28c

1.1

4.14d

1.20c

3.6

4.23c

1.17c

0

3.98d

1.23c

1.2

4.70e

1.27c

c,d,e Within each study, LDL-C, HDL-C, or Lp(a) concentrations that are significantly different between treatment groups have a different superscript.

cholesterol ratio would not be different from that to decrease LDL cholesterol concentrations.

Lp(a) Concentrations. Lipoprotein(a) (Lp(a)) concentrations in plasma have been associated with increased risk for developing cardiovascular and cerebrovascular disease, possibly via inhibition of plasminogen activity (Lippi and Guidi, 1999; Nielsen, 1999; Wild et al., 1997). Lp(a) is a lipo-protein particle similar to LDL with respect to its cholesterol and apolipoprotein B100 content, but it also contains an additional apolipoprotein termed apo(a) (Lippi and Guidi, 1999; Nielsen, 1999). Lp(a) concentrations have been reported by some investigators to be increased after the consumption of diets enriched in hydrogenated fat/ trans fatty acids (Tables 8-9, 8-10, and 8-11) (Almendingen et al., 1995; Aro et al., 1997; Lichtenstein et al., 1999; Mensink et al., 1992; Nestel et al., 1992b; Sundram et al., 1997), but not by all (Chisholm et al., 1996; Judd et al., 1998; Lichtenstein et al., 1993; Louheranta et al., 1999; Müller et al., 1998). The magnitude of the mean increases in Lp(a) concentrations reported to date that is associated with trans fatty acid intake for the most part would not be predicted to have a physiologically significant effect on cardiovascular disease risk. However, an unresolved issue at this time is the potential effect of relatively high levels of trans fatty acids in individuals with initially high concentrations of Lp(a).

504 DIETARY REFERENCE INTAKES

Hemostatic Factors. The effect of trans fatty acids on hemostatic factors has been assessed by a number of investigators (Almendingen et al., 1996; Mutanen and Aro, 1997; Sanders et al., 2000; Turpeinen et al., 1998; Wood et al., 1993b) (Table 8-12). In general, these researchers have concluded that hydrogenated fat/ trans fatty acids had little effect on a variety of hemostatic variables. Similarly, Müller and colleagues (1998) reported that hemostatic variables were unaffected by the substitution of a vegetable oil-based margarine relatively high in saturated fatty acids when compared with a hydrogenated fish oil-based margarine.

Susceptibility of LDL to Oxidation. Hydrogenated fat/ trans fatty acids have consistently been reported to have little effect on the susceptibility of LDL to oxidation (Cuchel et al., 1996; Halvorsen et al., 1996; Nestel et al., 1992b; S0rensen et al., 1998) (Table 8-12).

Blood Pressure. A few reports addressed the issue of trans fatty acid intake and blood pressure (Mensink et al., 1991; Zock et al., 1993) (Table 8-12). The authors concluded that consumption of diets high in saturated, mono-unsaturated, or trans fatty acids resulted in similar diastolic and systolic blood pressures.

CHD. Similar to saturated fatty acids, there is a positive linear trend between trans fatty acid intake and LDL cholesterol concentrations (Judd et al., 1994; Lichtenstein et al., 1999; Zock and Katan, 1992). Some evidence also suggests that trans fatty acids result in lower HDL cholesterol concentrations (Table 8-13). Hence, the net result is a higher total cholesterol or LDL cholesterol:HDL cholesterol ratio (Judd et al., 1994; Lichtenstein et al., 1999; Zock and Katan, 1992). This finding, combined with data from prospective cohort studies (Ascherio et al., 1996; Gillman et al., 1997; Hu et al., 1997; Pietinen et al., 1997; Willett et al., 1993) (Table 8-13), has lead to the concern that dietary trans fatty acids are more deleterious with respect to CHD than saturated fatty acids (Ascherio et al., 1999).

Summary

Similar to saturated fatty acids, there is a positive linear trend between trans fatty acid intake and LDL cholesterol concentration, and therefore increased risk of CHD. A UL is not set for trans fatty acids because any incremental increase in trans fatty acid intake increases CHD risk. Because trans fatty acids are unavoidable in ordinary, nonvegan diets, consuming 0 percent of energy would require significant changes in patterns of dietary intake. Such adjustments may introduce undesirable effects (e.g., elimination of commercially prepared foods and dairy products and meats that

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 505

contain trans fatty acids may result in inadequate intakes of protein and certain micronutrients) and unknown and unquantifiable health risks. It is possible to consume a diet low in trans fatty acids by following the dietary guidance provided in Chapter 11.

RESEARCH RECOMMENDATIONS

Total Fat

• Studies are needed that examine the effects of alterations in the level of total fat in the context of a low saturated fatty acid diet on blood lipid concentrations and glucose-insulin homeostasis in individuals with defined metabolic syndromes, such as type 1 and type 2 diabetes.

• Randomized and blinded long-term (greater than 1 year) studies are needed on the effect of dietary fat versus carbohydrate on body fatness.

Saturated Fatty Acids

• Further examination of intakes at which significant risk of chronic diseases can occur is needed.

• Data that examine the indicators for and risk of chronic disease at low levels of saturated fatty acid intake are necessary.

Cis-Monounsaturated Fatty Acids

• Information is needed to assess energy balance in free-living individuals who have implemented a diet high in monounsaturated fatty acids versus a diet lower in monounsaturated fatty acids (and higher in carbohydrate).

• Additional information is needed on the effects of alterations in the level of monounsaturated fatty acid in the context of a low saturated fatty acid diet on blood lipid concentrations and glucose-insulin homeo-stasis in individuals with defined metabolic syndromes, such as type 1 and type 2 diabetes.

• Studies are needed to evaluate cardiovascular disease risk status and risk of other chronic diseases in individuals consuming a high mono-unsaturated fatty acid diet versus a diet lower in monounsaturated fatty acids (and higher in carbohydrate).

• An evaluation of the nutritional adequacy and nutrient profile of free-living individuals following a self-selected high monounsaturated fatty acid diet is necessary.

• Studies that assess the effects of a high monounsaturated fatty acid diet on endothelial function and atherogenesis are needed.

DIETARY REFERENCE INTAKES

TABLE 8-12 Trans Fatty Acid (TFA) Intake and Blood Clotting, Low Density Lipoprotein (LDL) Oxidation, and Blood Pressure

Reference

Study

Population

Clotting Wood et al., 1993b

6-wk crossover,

37% fat Butter

Crude palm oil Margarine Refined palm oil Refined palm+sunflower Sunflower oil

Almendingen et al., 1996

3-wk crossover,

33-36% fat PHSO PHFO Butter

Mutanen and Aro, 1997

Turpeinen et al. 1998

80 men and women, 20-52 y

80 men and women, 20-52 y

5-wk crossover to 1 of 2 diets, 33-34% fat

High 18:0

High TFA

5-wk crossover to 1 of 2 diets, 32-34% fat 18:0 TFA

Sanders et al., 16 men and 1 test-meal crossover,

18:1 trans 24.7

MCT 0

Low fat 0

Oxidation Cuchel et al., 1996

14 men and women, 44-78 y

32-d crossover,

30% fat Corn oil

Corn oil+margarine

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 507

Resultsb Comments

TxB2 6-keto-PGF1a

36 100 62 95

Fibrinogen PAI-1 activity For PHSO, greater PAI-1 activity than PHFO

3.0 13.5 Increased fibrinogen with butter diet 2.9 10.7 No significant difference in factor VII,

3.1 8.8 fibrinogen peptide A, ß-thromboglobulin, or tissue plasminogen activator

No marked difference in factor VII

Fibrinogen coagulation activity, tissue type

(g/L) plasminogen activity, or PAI-1 activity 3.62 3.61

No difference in TXB2 production or ADP-

induced platelet aggregation in vitro Significant increase in collagen-induced aggregation with 18:0 diet

FVII FVII No significant differences in factor VII

(% standard) (ng/mL) coagulation activity; factor VII-activated

124 2.7 concentrations were significantly higher

122 1.9 with 18:1, 18:1 trans, 18:0, and 16:0 diets

114 1.9

112 2.1

112 1.5

No difference in susceptibility to LDL oxidation

508 DIETARY REFERENCE INTAKES

TABLE 8-12 Continued

Study

TFA (% of

Reference

Population

Diet"

energy)

Halvorsen et al.,

29 men,

19-d crossover,

1996

21-46 y

33-36% fat

Butter

0.9

PHSO

8.5

PHFO

8.0

S0rensen et al.,

47 men,

4 wk, consumed 30

1998

29-60 y

g/d of 1 of 2

margarines

mol % of fat

Sunflower oil

0.79

Fish oil, enriched

0.98

Blood pressure

Mensink et al.,

59 men and

3-wk crossover,

1991

women,

39-40% fat

19-57 y,

18:1

0

normo-

TFA

10.9

tensive

SFA

1.8

Zock et al.,

55 men and

3-wk crossover,

1993

women,

40-43% fat

19-49 y

18:2

0.1

18:0

0.3

TFA

7.7

a PHSO = partially hydrogenated soybean oil, PHFO = partially hydrogenated fish oil, MCT = medium-chain triacylglycerol, SFA = saturated fatty acid.

a PHSO = partially hydrogenated soybean oil, PHFO = partially hydrogenated fish oil, MCT = medium-chain triacylglycerol, SFA = saturated fatty acid.

n-6 Polyunsaturated Fatty Acids

• In metabolic and large observational studies, comparison should be made of the benefits of a-linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) across a range of n-6 polyunsaturated fatty acid intakes.

• Using good biomarkers for low density lipoprotein oxidation and cancer susceptibility, assessments are needed of the potential adverse effects of diets at levels of n-6 polyunsaturated fatty acids greater than 10 percent of energy.

• Studies that assess the effects of a high n-6 polyunsaturated fatty acid diet on markers of endothelial function and inflammation are needed.

DIETARY FATS: TOTAL FAT AND FATTY ACIDS 509

Results b

Comments

Dienes

Formation rate

No significant differences in conjugated

(nmol/mg

(nmol/mg

dienes, lipid peroxides, uptake by

LDL)

LDL X min)

macrophages, or electrophoretic mobility

1,020

10

of LDL

1,034

10

TFA does not alter susceptibility to LDL

1,107

10

oxidation

Oxidation rate

Fish oil consumption compared with

Dienes

(nmol/mg X

sunflower oil margarine had no effect on

(nmol/g)

min)

LDL size and led to minor changes in LDL

445

10.4

oxidation resistance

468

10.2

No effect of TFA intake on blood pressure

SBP (mmHg)

DBP (mmHg)

113

66

112

67

112

67

No effect of TFA intake on blood pressure

SBP (mmHg)

SBP (mmHg)

114

68

113

70

113

69

b TXB2 = thromboxane B2, 6-keto-PGF1a = 6-keto-prostaglandin F1a, PAI-1 = plasminogen activator inhibitor type 1, FVII = factor VII coagulant activity, FVII = factor VII activated, SBP = systolic blood pressure, DBP = diastolic blood pressure.

• Further research is needed to address the potentially important relationships between the amount of n-3 and n-6 fatty acids and glucose tolerance suggested by studies of fatty acid composition in affected individuals.

n-3 Polyunsaturated Fatty Acids

• Randomized clinical trials are needed of EPA+DHA, EPA, and DHA to evaluate their impact on cancer (i.e., colon, breast, prostate). The use of biomarkers for cancer susceptibility may expedite such studies.

DIETARY REFERENCE INTAKES

TABLE 8-13 Dietary Trans Fatty Acids (TFA): Epidemiological Studies

Reference

Study Design a

Dietary and Other Information

Lipoprotein concentration

Siguel and

Lerman, 1993

47 CAD cases 56 controls Case-control

No dietary intake information

Coronary heart disease (CHD) Hudgins et al., 1991

76 men, 23-78 y Cross-sectional

No dietary intake information

Troisi et al., 1992

Cross-sectional

Food frequency questionnaire, multivariate analysis

Willett et al., 1993

Women, 431 CHD cases Cohort, 8-y follow-up

Food frequency questionnaire, multivariate analysis

Ascherio et al., 1994

239 MI cases 282 controls Case-control

Food frequency questionnaire, multivariate analysis

Kromhout et al., 1995

12,763 men,

40-59 y Cohort, 25-y follow-up

Weighed food record

Ascherio et al., 1996

43,757 men,

40-75 y Cohort, 6-y follow-up

Food frequency questionnaire, multivariate analysis

DIETARY FATS: TOTAL FAT AND FATTY ACIDS

Results4

Commentsc

Plasma

Case

Control

TFA negatively associated with HDL

TFA (%)

1.38

1.11

TFA positively associated with LDL and

HDL (mmol/L)

0.88

1.34

TAG

LDL (mmol/L)

3.78

2.97

TAG (mmol/L)

1.78

0.97

Total TFA in adipose tissue was 4.4% of total fatty acids

Total TFA content in adipose tissue was not significantly related to risk factors of CHD (e.g., age, BMI, LDL, cholesterol, blood pressure)

TFA intake was directly related to total (

Arthritis Relief and Prevention

Arthritis Relief and Prevention

This report may be oh so welcome especially if theres no doctor in the house Take Charge of Your Arthritis Now in less than 5-Minutes the time it takes to make an appointment with your healthcare provider Could you use some help understanding arthritis Maybe a little gentle, bedside manner in your battle for joint pain relief would be great Well, even if you are not sure if arthritis is the issue with you or your friend or loved one.

Get My Free Ebook


Post a comment