Quantities of meat, dairy and eggs eaten tend to rise in line with increasing levels of affluence and falling prices. This trend is common in many countries in the Asia region, particularly in the last 20-30 years. The change in dietary patterns has prompted scientists to examine if there are any negative health effects, and this in turn has led to concern amongst some consumers. However, most scientists agree that lean meats, low fat dairy products, eggs and fish are all valuable components of a balanced diet partly because animal foods are particularly rich sources of some essential nutrients such as protein, iron, zinc and the 'zoochemicals'. Furthermore, these healthful substances are generally present in animal-derived foods in forms which are well absorbed by the body. In general current scientific opinion tends to recommend a diet in which moderate quantities of high quality, low fat animal-derived foods are balanced with generous quantities of plant-derived foods, preferably whole grain.  

Maximising Absorption of Nutrients

Absorption of some nutrients can be very variable, and the human body tends to use nutrients from animal-derived foods more efficiently than plant foods. The body's ability to use the nutrients in food however, can be altered by the combination of foods eaten together. So here are a few food combination tips to help your body get maximum benefit from the nutritional quality of foods consumed. 

·         The body can absorb more of the iron present in meat and fish than the iron in plant foods, but combining even a small amount of meat or fish with iron-rich plant foods, will increase the body's ability to absorb the iron from the plant foods.   

·         To improve the amount of iron the body can extract and absorb from plant foods, eat foods high in vitamin C such as orange, tomato and most green vegetables or their juices at the same time.  

·         Avoid or limit bran intake when consuming iron-rich plant foods because bran acts like a sponge preventing the body from absorbing the iron in these foods. 

Proteins: Consider Quality and Quantity

The proteins in the food we eat are broken down by digestion into amino acids. Amino acids are the building blocks from which our bodies are built - our flesh and blood. The human body requires quite small amounts of protein most of the time, but quantities needed for optimum health rise during some life stages, such as rapid growth in infancy, adolescence, pregnancy and after illness or injury when the processes of repair increase demand. 

Proteins from animal sources, such as meat, poultry, fish, eggs and dairy, provide all nine essential amino acids in proportions very close to the needs of the human body. Proteins from plants, legumes, grains, nuts, seeds, and vegetables, with the exception of soybeans, tend to be deficient in one or more of the essential amino acids. Soybeans are unique in the edible plant world, because soy protein, like animal proteins is made up of all the essential amino acids in just the right proportions that the human body needs. 

Vegan and vegetarian diets therefore can be balanced by combining foods that together provide the nine essential amino acids in these correct proportions, or by including adequate amounts of soy protein in the diet.  

Vital Vitamins and Mighty Minerals

Because of the small amounts needed, vitamins and minerals are referred to as micronutrients. (carbohydrate, protein and fat which, are needed in much larger amounts are described as macronutrients.) Animal foods tend to be excellent sources of some minerals and vitamins, particularly iron, zinc, iodine, vitamins A and D, and some of the B vitamins. 

B Vitamins

The B group vitamins have many functions, including the breakdown of proteins to form red blood cells. They can be found in dairy, eggs, meat, chicken, fish and dark leafy green vegetables, legumes, nuts and whole grains. 

Vitamin A

This vitamin is important for healthy skin, immunity and eye health. High concentrations can be found in liver, kidney, egg yolk, dark green leafy vegetables, orange and yellow vegetables and fruits. 

Vitamin D

Vitamin D helps to maximize calcium use and maintain bone health. Exposure to sunlight is a primary source for many, but for those with limited exposure to sunlight; fish oils, egg yolk and some fortified dairy products are important in ensuring the body’s stores are adequate. 

Calcium

Calcium gives strength to bones and teeth. It is also essential for many other normal body processes, such as blood clotting and in the regulation of muscle function. Calcium needs increase substantially in periods of rapid growth such as childhood, adolescence, pregnancy and also for breast feeding mothers. High concentrations of calcium can be found in dairy, sardines and canned salmon with bones, almonds, figs, calcium-enriched tofu and some dark green vegetables. 

Iron

Iron is needed for the synthesis of haemoglobin (the red pigment in blood which carries oxygen to all the body's cells). The human body can absorb the form of iron which is found in meat and poultry, known as heme iron more efficiently than the form of iron, found in fruits, vegetables and grain products, known as non-heme iron. Typically the body extracts about 25% of heme iron in a food compared to only 10% of non-heme iron.  

Zinc

Zinc is needed for the breakdown of carbohydrates, fats and proteins in the digestive system, immune functioning and wound healing.  The most concentrated sources of zinc include red meat, eggs, poultry, and shellfish. Whole grains in cereals or bread, as well as nuts and legumes, are other good sources, but are not so efficiently absorbed by the body. 

Iodine

This is needed by the thyroid gland which is involved in regulation of growth and metabolism and is found in sea fish and iodised table salt. 

The Beneficial  New 'Zoo's'

There are increasing levels of interest amongst scientists in other substances found in animal foods which are not essential and are therefore not classified as nutrients, but which do seem to offer specific, additional health benefits. These are sometimes referred to as "zoochemicals." Emerging research on the potential health benefits of some of these zoochemicals looks very promising. 

Conjugated Linoleic Acid

Preliminary research suggests that Conjugated Linoleic Acid (CLA) may not only suppress cancer cell development, but may also help reduce risk of heart disease, boost the immune system, build lean muscles, and diminish body fat. CLA is found in meat and dairy products.  

Lutein and Zeaxanthin

These two compounds appear to improve eye health, specifically protecting against age related macular degeneration, the leading cause of blindness in the elderly. Green leafy vegetables are the best plant source, but egg yolks are an even more concentrated source.                                               

Omega-3 Fatty Acids

Omega-3 fatty acids are found in cold-water oily fish such as salmon, trout, mackerel, tuna and eggs from poultry fed a diet enriched with omega-3 fatty acids. Fish is the most concentrated source, but some plant foods, for example seaweed, flaxseed and walnuts are also good sources.  Also there is a range of new omega-3 fortified products becoming available to shoppers, which can provide a useful additional source of this important group of compounds. Omega-3 fatty acids are vital for brain and eye development in infants. There is also very compelling evidence that a diet rich in omega-3 fatty acids protects against  coronary heart disease, Type 2 diabetes, Alzheimer's disease and some other chronic long term illnesses.