Nutrition Facts

The cosmetics market is full of skin care products of herbal as well as many other products. Most of the skin care products are of herbal based and aloe vera is one of the commonest ingredients. Aloe vera is excellent in skin care; it moisturizes the skin, removes the wrinkles of skin and helps in restoring the natural glow of the skin. There are also many more herbal ingredients that are excellent in skin care.

The skin care products are of many types like acne scar cream, scar cream, acne treatment cream, anti stretch mark cream etc. to name a few. The skin care products takes about a month to be effective and another month to be fully effective and that is the reason many products are available as one month pack and another month’s pack is provided free of cost, so that the maximum effect of the skin care product can be seen and the user can be assured of the quality of the product.

Among the skin care herbal products anti wrinkle face creams are most widely used products. The anti wrinkle face creams use aloe as base instead of water (water and oil are the commonest bases used). Anti wrinkle face creams use vitamins (mainly retinol or vitamin A, vitamin C, vitamin E etc.) and peptides as the main ingredients. The anti wrinkle face creams are devoid of minerals and propylene glycol. Aging starts at the deep of the skin and as we age the turn around time of the cells of the skin begins to shortens. The anti wrinkle face creams help to maintain the turnaround time and thus reduce the wrinkle of the skin.

Vitamin A is actually retinol. But for practical purpose it also include a pro vitamin, pre formed vitamin, beta carotene, retinoic acids, retinaldehyde oxidized metabolites etc. other than retinol. Some of the above are converted to retinol in the intestinal mucosa. The term retinoid include all the molecules that are chemically related to retinol. Retinaldehyde is the essential form of vitamin A that is required for normal vision and retinoic acid is necessary for normal morphogenesis, growth, and cell differentiation in our body.

The unit of vitamin A at present is “retinol activity equivalent” (RAE) and this is very convenient to use than the older form of IU (international unit). IU was in use before 1954 and after 1960 the unit “retinol” is used for vitamin-A alcohol that is available in crystalline form. 1 IU of vitamin A is equal to 0.03 microgram (mcg) of retinol. The following is the conversion:

1 microgram of retinol = to 1 mcg of RAE

1 mcg of carotinoid (beta carotene) = 0.084mcg of RAE

Vitamin A is commercially available in esterified forms (e.g., acetate, palmitate), because they are more stable forms of vitamin A.

There are more than 600 carotinoids available in the nature and out of that about 50 of them can be converted to or metabolized to vitamin A. Beta carotene is the commonest form of carotinoid that is available in our food with pro vitamin activity. In humans large percentage of carotinoids are absorbed and stored in liver and fat deposits.

Vitamins are the group of organic compounds that can not be synthesized by our body but are essential for our body and must be supplied in the diet (exceptions are vitamin D is synthesized in our skin when exposed to sunlight and small and insufficient quantity of vitamin K is synthesized in the intestine by intestinal flora). Vitamins can not be synthesized but are essential nutrients for us. Vitamins are required by us in very small quantity and fall in the category of micronutrients.

Vitamins do not give us any calorie or energy but helps the body for utilizing other nutrients. Since our body is unable to synthesize vitamins (even if synthesized they are not sufficient), they must be supplied in our diet. A well balanced diet can provide us all the vitamins and other nutrients both major (proteins, fats and carbohydrates) and minor (vitamins, minerals and trace elements or trace minerals).

Vitamins are broadly divided into two groups: (a) Fat soluble vitamins that include vitamin A, D, E and K and (b) Water soluble vitamins that include B complex group of vitamins and vitamin C. Vitamin B complex group include vitamin B1 or thiamin (thiamin is the first B complex vitamin to be discovered and named as B1), B2 or riboflavin, B3 or niacin, B6 or pyridoxine, B5 or pantothenic acid, folic acid and vitamin B12, the group also includes choline and flavoniods.

Each of the vitamins has one or more specific functions to perform and deficiency of any of the vitamins can lead to specific deficiency disease (except vitamin E, any deficiency disease is yet to be identified if it is there, but it helps in making the skin glow), e.g. deficiency of vitamin C leads to scurvy (very well known).

The minimum intake of vitamins per day has been determined but the daily optimum intake is still not clear and is still speculative. So the recommended daily allowance of vitamins is in speculative stage.

Fats are foods that provide us with calories and they are always equated with calories due to their high calorie yielding capability. Fats are high energy foods and provide us as much as 9 kcal of energy per gram. The functions of fats can be summarized as:

1. Fats supply high calorie and spare the proteins for being used as source of energy.
2. Fats act as a vehicle for fat soluble vitamins (vitamin A, D, E & K).
3. Fats in the body support important viscera like heart, kidney, intestine etc. and fats beneath the skin (subcutaneous fat) provide insulation against cold.
4. Essential fatty acids (EFA) are required for our body growth, for structural integrity of cell membrane and to reduce platelet adhesion (important in preventing heart attacks). Essential fatty acids also reduce cholesterol and low density lipoproteins (LDL).
5. Many polyunsaturated fatty acids are precursors of prostaglandins which are a group of compounds that are known as “local hormones” and play an important role in physiological functions of the body like kidney functions, acid secretions in the stomach, vascular homeostasis, gastro intestinal motility, lung physiology and reproductive function.
6. Cholesterol (a fat which is disliked by us due to its role in cardiovascular diseases) is a very important fat for us. Cholesterol is essential for synthesis of bile acids and steroid hormones as it is the precursor for the synthesis of steroid hormones and bile acids.
7. Fats provide palatability to our food and without the fat food is of limited palatability.
8. Fats are stored in our body to supply energy during the lean period and help us survive malnutrition and likes of famines in the history of mankind as it is serving the same purpose to the animals at present.

Thus fats serve many important functions for us. But the non-calorie functions of fats have been discovered only recently.

Fats are present in a variety of sources and humans obtain fat mainly from three sources which are categorized below. It is present in both animal and plant foods. The dietary sources of fats can be grouped under three broad groups and they are fats from animal sources, fats of plant sources and others.

1. Fats of animal origin: This is one of the major sources of fat for human diet. Among the animal sources of fat includes butter, ghee, cheese, egg, milk and fats of meat (red meat like pork, beef, mutton etc. and white meat like chicken, fowl, duck etc.) and fish (both fresh water fish and salt water fish). Fats of animal origin are mostly of saturated fat type. But there are exceptions like fish oil, cod liver oil and sardine oil which are very rich sources of unsaturated fats (omega3 fatty acids). That is why fats of animal origin except few exceptions are considered unhealthy for humans which cause cardiovascular disorders.
2. Fats of Plant/Vegetable Origin: This is another major source of fat for humans. The major sources of fat of plant or vegetable origin are seeds (fat is stored in plant seeds) mainly oil seeds, peanut, mustard, sunflower, coconut, olive etc. fats of vegetable origin are mainly unsaturated (both mono unsaturated and poly unsaturated fats) type with only exception being coconut oil which contain very high unsaturated fats comparable to fats of animal origin, so not healthy for humans. Because of high concentration of unsaturated fats or fatty acids the fats of plant origin are considered superior than animal fats and healthy for human consumption.
3. Other Sources: Fats of other sources include the small quantity of “invisible fats” which are present in most of the foods like cereals, pulses and vegetables. For example rice contain 3 per cent of fat, wheat also contain 3 percent of fat. They are called “invisible fats” because they are very small in quantity, not visible to naked eye and very difficult to calculate and are ignored, but this “invisible fats” constitute a good proportion of fat intake by humans particularly in developing countries, because in developing countries cereal and vegetable consumption is very high. Other sources of fat also include the fat which is converted from carbohydrate in our body.

The “invisible fats” which is consumed in developing countries may contribute more amount of fat that the visible fat (visible fats are the fats which are separated from their natural sources).

Fats or lipids are solid at 20 degree Centigrade and fats are called “oils” if they are liquid at that temperature (20 degree centigrade). Fats and oils are very high source of energy and yield 9 kcal of energy per gram (compare to other two major sources of energy, carbohydrates and proteins which both yield about 4 kcal of energy per gram). Fats can be classified as (a) simple lipids like triglycerides, (b) compound lipids like phospholipids and (c) derived lipids like cholesterol.

Our body can synthesize cholesterol and triglycerides endogenously (within our body). Almost all of our body fat (about 99%) is stored in adipose tissue in the form of triglyceride. One kilogram of adipose tissue is equivalent to about 7700 kcal. So for loosing weight one has to burn 7700 kcal of energy just to loose 1 kg of body weight and loosing weight become extremely difficult. Adipose tissue constitute about 10-15 percent of body weight in normal subjects.

Fatty acids

Fats on hydrolysis convert to fatty acids and glycerol. There are two types of fatty acids, saturated fatty acids and unsaturated fatty acids. Examples of saturated fatty acids are palmitic acid, stearic acid, lauric acid etc. Unsaturated fatty acids are further subdivided into mono unsaturated fatty acids (e.g. oleic acid) and poly unsaturated fatty acids (e.g. linoleic acid, linolenic acid, arachidonic acid etc.).

Animal fats contain very high percentage of saturated fatty acids and are not good for health. Polyunsaturated fatty acids are mainly of vegetable origin and good for health. But there are exceptions to this rule and fish oil contain large percentage of mono and polyunsaturated fatty acids (omega-3 fatty acids) and some vegetable oils like coconut oil and palm oil contains high percentage of saturated fatty acids. So palm oil and coconut oil are not good for health but animal fat like fish oil is very good for health.

The sources of protein can be divided into two broad categories animal source and plant or vegetable source. Both of the sources are important source for supply of protein in our diet, depending on the cultural practice, religious belief, availability and locality.

Animal sources:

The important sources of animal protein include eggs, meat, fish, cheese and milk. The animal proteins contain all the essential amino acids and the quantity of these essential amino acids is adequate in animal protein. Essential amino acids have to be supplied in our diet as they can not be synthesized by our body.

The egg proteins are considered best among all the food proteins as egg protein has highest “biological value” and digestibility. For this quality the egg protein is used as “reference protein”.

Vegetable sources:

The rich sources of vegetable protein are pulses (lentils etc), cereals (rice, maize, wheat, millets etc), nuts, beans etc. In developing countries the vegetable proteins are the main source of protein in the diet. The vegetable source proteins are poor in essential amino acids. They are deficient in one or more essential amino acids. These are known as “limiting” amino acids. But combination of two or more vegetable protein compensates the deficiency of the essential amino acids. For example cereal protein (rice, wheat etc.) is deficient in lysine and threonine and pulse protein is deficient in metheonine. Here lysine, threonine and metheonine are the “limiting” amino acids. But when these two sources (here rice/wheat and pulse) are combined in the diet they compensates each other and make the whole of the protein “biologically complete”.

Proteins are made up of smaller units known as amino acids. The protein molecules are made up by joining many amino acids and forming a chain or tree like structure. Many amino acids are there which are required by human body. The total number of amino acids required by human body is 24. And out of the 24 amino acids 9 of them are known as essential amino acids as they are required by our body but our body can not synthesize them and if they are synthesized also the quantity is not sufficient for our need. That is why the essential amino acids have to be supplied in our diet.
The essential amino acids are leucine, isoleucine, lysine, methionine, phenylalanine, threonine, valine, histidine and tryptophan. For synthesis of protein for our body tissues both essential and non essential amino acids are required. The essential amino acids must be supplied in our diet, but the non essential amino acids can be synthesized by our body if the required building blocks are present.
Functions of essential amino acids:

1. Essential amino acids are required for the synthesis of body proteins that include important proteins like enzymes, antibodies, immunoglobulins or Ig (IgG, IgM, IgE etc.), hemoglobin etc.
2. Essential amino acid tryptophan is required for the formation of niacin which is a B complex vitamin. Niacin is synthesized from tryptophan. Niacin deficiency causes pellagra.
3. Essential amino acid methionine acts as a donor of methyl groups for synthesis of choline, folic acid (a vitamin) and nucleic acids.
4. New tissue can not be formed if all the essential amino acids are present in our diet.
5. Essential amino acids cystine and tyrosine are essential for premature babies.

A protein is “biologically complete” if all the essential amino acids are present in that protein in amounts corresponding to our needs. If one or more essential amino acid is absent or lacking in amounts corresponding to our needs, the protein is said to be “biologically incomplete”. The quality of protein or biologically complete or incompleteness is closely related to pattern of the amino acids. In general, animal proteins are of better quality than vegetable proteins because they are biologically complete. Egg proteins and milk proteins have amino acid pattern which is most suitable for human needs. Vegetable proteins lack in one or more amino acids, so they are biologically incomplete. But if two or more vegetable proteins are combined they compensate the deficiency of each others (deficiency of essential amino acids) and become more biologically complete.

The word protein is derived from – and the meaning of protein is “of first importance”. Proteins are indeed the most important in human nutrition. Proteins are complex organic substances containing nitrogen in its molecule. Proteins differ from carbohydrates and fats form the fact that they contain nitrogen. The nitrogen content in protein is approximately 16%. Proteins contain carbon, hydrogen, oxygen, nitrogen and sulphur in its molecule in varying amount. Some of the proteins contain phosphorus, iron (hemoglobin is classical example of protein containing iron) and sometimes other elements. Proteins are very large molecules with very high molecular weight (largest organic molecule) and made up of many smaller units called amino acids. About 20% of adult body weight is made up of protein.
Functions of Proteins:
Proteins are required for the following major functions:

1. Proteins are required for growth and building of body and proteins are body building materials. This is very important for the growing children and infants. But this is very small component of function of protein in compare to the maintenance proteins do everyday continuously.
2. Repair and maintenance of body tissue is the most important and extensive function of proteins. Proteins are required for healing of wounds, any damage of tissue. Any ware and tear is repaired by proteins which is a constant process.
3. Maintenance of plasma oncotic pressure is also function of proteins. Without normal plasma oncotic pressure there will be no perfusion and diffusion of chemicals.
4. Proteins can supply energy of 4 kcal of energy per gram if there is inadequate supply of calorie, but supply of energy (calorie) is not primary function of protein.
5. Synthesis of important substances like antibodies, immunoglobulin, hemoglobin, hormones, enzymes, plasma proteins, coagulation factors and many more. All of these are proteins. They perform very important functions. Antibodies and immunoglobulins fight with bacteria and other foreign invaders and protect body from diseases. Hemoglobin carries oxygen and supply to tissues which is vital for survival. Hormones are very important for normal functioning of humans. Enzymes are required for all the chemical reactions that take place in the body. Plasma proteins maintain oncotic pressure and also supply proteins where it is required. Coagulation factors are required for control of blood loss from injury or cut surface.

Other than the above mentioned functions, proteins also have some minor functions. The bactericidal (killing of bacteria) action of white blood cells is hampered if there is protein deficiency. Cell mediated immunity is also hampered in protein deficiency states. Both of the above conditions are seen in protein energy malnutrition (kwasiorkar and marasmas).

Nutrition is a science of food and relationship of food science with health. Nutrients are substances that must be supplied in sufficient quantity in the diet because they can not synthesized by our body. Nutrients are required for body growth and development and for maintenance of normal body function. Nutrients are also known as “food factors”. Nutrients are proteins, fats, carbohydrates, vitamins, minerals and trace elements which are required by our body in micro quantity but are essential for growth and maintenance of normal body functions. Water is also can be classified as nutrient and it is one of the most important and without it a man will not survive. Without food a man can survive for more than a month but with out water a man can not even survive for a week. And these days water pollution is a major concern that can affects health adversely.

Dietetics is the practical application of principles of nutrition. Dietetics includes planning of food and nutrition for diseased or sick and for people with normal health. Dietetics also includes planning of diet for weight loss for the overweight (a body mass index or BMI of more than 25-30) and obese (BMI of more than 30) persons. Dieticians are the person who deals in dietetics and do the planning of food intake in diseased state, for healthy persons who want to maintain good health and for overweight and obese who want to get to normal body shape.

For optimum health we need energy providing foods, which are proteins, fats and carbohydrates, vitamins, which include 4 fat soluble vitamins (vitamin A, D, E and K) and 10 water soluble vitamins (vitamin B complex group, folic acid and vitamin C), choline, 4 minerals, 7 trace elements or minerals, 3 electrolytes and few ultra trace minerals.

Someone is getting good nutrition can be said when he is having a nutritional status that enables him to grow well and maintain good health. Good nutrition is essential for growth and well being of individual and community as a whole. Without good nutrition a nation can not prosper and it is the very basic for the development of a nation as a whole.