we lose lots of nutrients like protein, fat, amino acids, thiamine, Nicotinic acid unknowingly with our regular activities, Nearly all foodstuffs with the exception of fruits and some leafy vegetables used either as salads or chutneys are consumed after cooking.

Cooking involves the following processes

• The wet methods of treatment like boiling and steaming.
• Dry methods of treatment like frying, roasting, and baking.

The wet methods of cooking lead to comparatively greater loss of vitamins than the dry methods.

Ordinary cooking causes little loss of nutrients in cereals, pulses, and meat. In vegetables, however, there may be some protein loss on boiling in water, particularly when salt is used in cooking and the cooking water is discarded. If the cooking water is thrown away there is considerable loss of mineral salts especially sodium, potassium, and chlorine due to leaching.

It is therefore advisable either to use the minimum amount of water or to utilize the cooking liquor in either soups or gravies.

Root Vegetables do not suffer much loss in nutrients by either wet or dry methods of cooking, because the skin of most root vegetables prevents leaching out of the nutrients. It is, therefore, preferable to boil them with their skins on.

Methods of Cooking:

Loss of Nutrients in cooking & cleaning process:

• A certain amount of minerals and vitamins are lost even during preliminary treatment of washing prior to cooking. It is common for housewives to wash rice three or four times with large amounts of water before cooking. Rice of poor commercial quality naturally requires more washing than rice of good quality does, and in the process, there is a loss of minerals. The B vitamins especially thiamine and nicotinic acid are also lost to the extent of about 40%. The rice broth is strained away along with a part of vitamins after cooking rice.
• However be mentioned that broth though it carries a small portion of the vitamins and minerals contained in the original rice, is not as high in nutritive value as is generally believed. It will be a good practice to wash the rice only if necessary with the least quantity of water and cook it in just a sufficient amount of water so that all the water is absorbed and no broth is discarded.
• More than the minerals, it is the vitamins particularly the members of the water-soluble group that show a greater loss as a result of cooking.
• Vitamin A or carotene is not affected when foodstuffs are cooked in water. But in shallow frying or roasting, there may be considerable loss of vitamin.
• The loss in thiamine due to cooking may be occasioned partly by destruction during cooking and partly by the dissolution of the vitamin in the cooking water. If excess water is used and the cooking water is discarded, a loss of  50% of the vitamins can occur. Further, if cooking soda is added especially while cooking dhal’s or pulses to facilitate cooking or to preserve the color of the dhal, most of the thiamine is destroyed.
• Conversely, a substance like a tamarind with high acidity, if added to cooking water has a preservative effect on the vitamins. 
• Since in most houses a dish is rarely consumed immediately after cooking, it is desirable to include some raw fruit or vegetables in the diet as a source of Vitamin C.
• Milk is a poor source of Vitamin C  and a major portion of this vitamin is lost in boiling.
• Eggs appear to suffer little loss in nutritive value as a result of the conventional methods of cooking.

Every nutrient is important to our body, so let’s utilize whatever we get through natural resources rather than taking them artificially later.