What nutrients are

We depend for sustenance on what we consume, but fortunately we are not what we eat! The foods that we eat and drink are broken down by grinding and digestion, sorted by selective absorption, and changed in metabolic reactions. The it It ¡mate late of an absorbed compound in the body depends on how quickly it is metabolized for energy production or excreted with bile or urine. Most ingested compounds leave again after a short time-which is for the better. Some of those that insist on staying on (pesticides, toxic heavy metals, too much fat) are unwelcome guests that make us wish for more short-term \ isitors like vitamin C (ascorbic acid) that cheerfully do their job and leave again in a timely manner.

Nutrients are compounds from foods and bacterial production in the gut that the body-uses for its normal (physiological) functions. This broad definition includes compounds that are utilized dirccily for energy production (ethanol >. to aid in metabolism (coenzymes), lo build body structures (cholesterol), or to serve in a specific cellular function (bromine for the oxidative burst of eosinophils). A nutrient has been considered essential in short-lived organisms if its lack prevents the organism from completing its life cycle and if the compound is directly involved in the function of the organism (Hpstein. 1994), This definition has some obvious shortcoming for humans, because many of current concerns are about health long beyond reproduce e age. Indeed, more than half of healthy people's life span is spent after cessation of reproduction (Blurton Jones el til.. 2002), Prevention of cardiovascular disease, cancer and dementia has come to the forefront of today's healthcare efforts. The significance of an individual's exposure to particular food compounds for a span of nearly a hundred years is just beginning to come into focus.

Handbook of Nulricnt Metabolism ISBN: I)-12-41 "762-X

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Essential building blocks

At least 26 different elements are used to build tlie human body and keep it functioning, and possibly a few more. Fourteen of them are usually found in quantities of at least a gram or more in a young 70 kg man. Fluorine (as lluoride) strengthens and protects teeth, possibly also bones, but is not considered essential. Additional elements, including tin. rubidium, germanium, and lithium, are consumed in small, but significant amounts with foods and are regularly present in the body. It is uncertain, however, whether these are truly needed at any stage in life or pro\ ide any health benefit (Nielsen. 2001).

The body can use several elements only when they are ingested as part of particular compounds. Carbon has to be supplied mainly as digestible carbohydrate, alcohol, fat or protein. Nitrogen has to be consumed as protein: small amounts of ammonia and some

Tabic 1.1 Oemenra of the body

Intake body concern

Tabic 1.1 Oemenra of the body

Intake body concern

(g/day)

(g/ 70 kg)

Oxygen

2000

45 000

Estimated

Carbon

305

16000

Estimated

Hydrogen

275

4000

Estimated

Nitrogen

10

4000

Estimated

Calcium

1

700

Food and Nutrition Board

Phosphorus

1

450

Alota eta!., 1984

Sulfur

0.3

200

Estimated

Potassium

3

140

Larssoo ei al, 2003

Sodium

3

100

Forbes, 1987

Chloride

6

95

Forbes, 1987

Magnesium

0.3

25

Elm, 1987: Rude, 2000

Fluorine

0.002

6

Whitford, 2000

Iron

0.008

3

Zinc

0.011

2

King and Keen, 1994

Copper

0.0009

0.1

Manganese

0.0002

0.1

Iodine

0.00015

0.02

Selenium

0.000055

0.017

Schroeder et at,. 1970

Molybdenum

0.0000-55

Chromium

0.000020

Cobalt

-

Bromine

Boron

Silicon

Arsenic

10

Vanadium

Nickel

Tin

Rubidium

Germanium

Lithium

Aluminum Cadmium I rail

Aluminum Cadmium I rail nitrogen compounds can also be utilized. Hydrogen comes with water and smaller amounts with nutrients. Sulfur has to come with methionine, cysteine, and sulfate. Phosphorus can be utilised only in the form of phosphate salts.

Understanding And Treating Autism

Understanding And Treating Autism

Whenever a doctor informs the parents that their child is suffering with Autism, the first & foremost question that is thrown over him is - How did it happen? How did my child get this disease? Well, there is no definite answer to what are the exact causes of Autism.

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