Question

A Vitamin Primer Learning Objectives: Discuss the dietary sources of vitamins. ; Describe how bioavailability affects vitamin requires.; Explain the function of coenzymes.; Describe the vitamin information provided on food labels.

Answer 1

Dietary Sources of Vitamins

There are various vitamins available in nature which are as follows:

1)Vitamin A

Sources of Vitamin A are milk, eggs, green vegetables, fruits such as apricots, peaches, papayas, and mangos.

2)Vitamin C

Sources of vitamin C is citrus fruits, strawberries, kiwi, guava, peppers, tomatoes, broccoli, and spinach.

3)Vitamin D

Sources of Vitamin are Sunlight, egg yolks, oily fish such as salmon, tuna, and milk

4)Vitamin E

Sources of Vitamin E are vegetable oils, nuts, and green leafy vegetables. Avocados, wheat germ, and whole grains are also good sources.

5)Vitamin B12

Sources of Vitamin B12 are fish, red meat, poultry, milk, cheese, and eggs.

6)Vitamin B1(Also known as Thiamin)

Sources of Vitamin B6 are fortified bread, cereals, and pasta; lean meats; dried beans, soy foods, and peas; and whole grains like wheat germ.

7)Vitamin B3(Also known as Niacin)

Sources of Vitamin B1 are red meat, poultry, fish, fortified hot and cold cereals, and peanuts.

8)Vitamin B6

Sources of Vitamin B6 are potatoes, bananas, beans, seeds, nuts, red meat, poultry, fish, eggs, spinach, and fortified cereals

9)Vitamin B2(Also known as riboflavin)

Sources of Vitamin B2 are meat, eggs, legumes (like peas and lentils), nuts, dairy products, green leafy vegetables, broccoli, asparagus, and fortified cereals.

10)Vitamin B9

Sources of Vitamin B9 are dried beans and other legumes, green leafy vegetables, asparagus bread, rice, and cereals.

Bioavailability

Bioavailability is the actual access or actual absorption of vitamins by intestinal membranes which is independent of the consumption of the food(vitamin sources).

Bioavailability can be affected by various factors such as:

a) Some enzyme stimulates vitamin absorption while other resists is

b)Ageing, toxicity may also be responsible for varying bioavailability.

c)Some vitamins may be required to undergo some conversion to become absorptive.

Function of Coenzymes

Coenzymes are small molecules that help enzymes to react faster by increasing its activity.

They generally accept atom from the substrate and transfer them to other molecules(like a carrier).

They are less selective than enzymes so that coenzymes helps in multiple reactions

Vitamin Info available on food labels

Various vitamins (along with other nutrients such as fats, proteins, carbohydrates etc.) which are present in the food is listed as % daily value which is an indication of the contribution of vitamins to the total daily diet.