Vitamins, Human Physiology, Diseases: Water, Balanced Diet and Deficiency Diseases

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Vitamins

VitaminsVitamins
VitaminsObservations leading to discoverySourcesDeficiency symptoms
Vitamin A

(Carotenoids)

Purified diets fail to support life and growth of childrenCarrot green vegetables, milk, butter, eggsRetardation of growth, night blindness
Vitamin B (Thiamine)Incidence of beriberi in people consuming polished diet.Yeast, germ of cereals, beans, eggs, liver, porkBeriberi, loss of appetite, cessation of growth
Vitamin B2 (Riboflavin)Presence of these factors in yeast besides thiamine.Yeast, milk, liver, eggs, vegetables, meatAnaemia, defective vision
Vitamins B2 (Niacin)Association of pellagra with maize consumption and deficiency of free nicotinic acid in maize.Meat, liver, chicken, yeastPellagra
Vitamin B6 (Pyridoxine)Skin lesions in rats even if supplied nicotinic acid and other nutrientsYeast, milk, liver cerealsAnaemia loss of weight.
Vitamin B12 (Cyanocobalamin)Value of liver in the treatment of pernicious anaemiaKidney, milk, liver, molasses, egg, meatPernicious anaemia
Vitamin C (Ascorbic acid)Scurvy in sailors living on diets lacking tomatoes, fresh fruit and vegetables.Fresh vegetables specially circus fruits, tomatoes.Scurvy, bleeding of gums.
Vitamin D (Calciferol)Children suffer from rickets if not exposed to sunlight adequatelyFish liver oil, yolk and milkRickets in children, bones become weak
Vitamin E (Tocopherol)Failure of reproduction in rats fed upon diet free of vitamin EWheat germ-oil, green vegetables, eggsLoss of fertility.
Vitamin K (Phylloquinone)Haemorrhages in animals fed on purified diets containing other extracted fish meat.Green leafy vegetables, liver, eggsBlood fails to clott quickly

Human Physiology, Diseases

Water

About 60% of the weight of the body is due to water. Water plays such a vital role in the physiology of living beings which no material can serve. The importance of water in our body is so great that even 10% of the water loss may prove fatal.

Balanced Diet

A diet which contains of all the essential food constituents՚ viz. protein, carbohydrates, fats, minerals, vitamins, water in correct proportion is called Balanced Diet. A balanced diet has following composition: (i) Carbohydrates 60% ; (ii) Proteins 25% ; (iii) Fats 15% . Individual Caloric Requirements: People doing different types of work need different calories of energy in a day. The energy requirement depends on the age, sex, nature of work and climate.

Deficiency Diseases

Calcium, iron, iodine, sodium, potassium, magnesium, phosphorous, chloride, is some of the common minerals essential for the normal physiological functioning of the body. Deficiency of these minerals results in the diseases. Few of them are discussed below:

Anaemia

It is caused by the deficiency of iron in the diet. Since iron is an important constituent of haemoglobin therefore there is deficiency of haemoglobin in the red blood corpuscles. Since haemoglobin plays a vital role in the transport of oxygen, enough oxygen is not made available to cells to oxidise the nutrients and production of energy. It is because of this reason anaemic patients look pale and get exhausted soon with little amount of work. The rich source of iron is liver, meat, green leafy vegetables (such as spinach) and fruits (guava, apple, banana, etc.) . These sources of iron if taken in diet can recover the patient from this ailment. The reason for higher incidence of anaemia in women than in men is menstrual loss, loss of blood during child birth etc.

Goitre

It is caused due to deficiency of Iodine. Due to iodine deficiency, the thyroid fails to synthesize enough amount of thyroxin. The low amount of thyroxin stimulates anterior lobe of pituitary to release Thyroid Stimulating Hormone (TSH) . The increasing amount of TSH in turn stimulates thyroid gland to enlarge. This enlargement of thyroid gland so as to secrete more of thyroxin is known as goitre. Cure: Those who live in areas where iodine content in water is low are advised to use iodized salt containing 0.01% Potassium Iodine.

Hypokalemia

It is caused due to deficiency of potassium. The body experiences deficiency of potassium due to (i) severe vomiting (ii) acute diarrhoea (iii) excessive secretion of the hormones of adrenal cortex.

Hyponatremia

It is caused due to deficiency of sodium. The body experiences deficiency of sodium due to (i) intense vomiting (ii) acute diarrhoea.