Dairy products play a vital role in a balanced diet regimen. Dairy products are the choice of researchers in the development of functional foods. Functional foods are foods that have some additional health benefits beyond their basic nutritional value, as some specific bioactive compound has been added to it. Functional dairy products have recently gained popularity among consumers in the past few years because of their desired health benefits.
Milk is considered a good source of all vital essential nutrients and almost a complete food that contains a good source of protein, fat, lactose, vitamins, and minerals. Dairy products form a considerable daily diet portion of the most susceptible group like old age, neonates, lactating mothers and infants. Milk is one of the best nourishment diet sources besides breast milk for new-borns and babies. Many functional dairy products have been recently developed and consumed all over the world including, fermented products, probiotic, prebiotic and symbiotic food. Their demand is increasing consistently and peoples are getting health benefits, because of their positive effect on overall health due to added bioactive ingredients.
Milk contains a variety of proteins, oligosaccharides and peptides, which are either the part of raw fresh milk or produced upon fermentation or digestion process. Some of the sphingolipids or their metabolite present in milk has been investigated to show antimicrobial effect also. The trace mineral bioavailability like selenium and manganese, iron and zinc etc., is also improved by milk proteins and peptides. Milk proteins and peptides play an active role in nutrient absorption and digestion.
The functional importance of probiotics and fermented dairy foods are either directly through consumed microorganisms or through the production of microbial metabolite from fermentation process. The health supporting mechanisms of probiotic drinks are through improving indigenous intestinal microflora and immune modulatory mechanisms.
As per guidelines of food and drug administration one serving of milk can provide the following recommended dietary daily values of nutrients. The basic physiological function associated with these nutrients on a broad basis are mentioned below:
Calcium (25 percent): Maintain strong bones and teeth
Riboflavin (35 percent): helps in cellular development of nervous system, skin, RBC and metabolism of fat and carbohydrate
Phosphorus (20 percent): help in muscle contraction and formation of genetic material (DNA and RNA), Strengthens bones, energy balance
Vitamin D (15 percent): calcium absorption, insulin regulation, anti carcinogenic activity
Pantothenic Acid (20 percent): acetyl CoA synthesis, important constituent of energy cycle
Potassium (8 percent): maintain fluid and electrolyte balance, blood pressure regulation and cardiovascular health Vitamin A (15 percent): Promotes good vision and healthy skin
Niacin (10 percent): reduce triglycerides and promote good cholesterol
Health Benefits of Dairy Foods
Many studies suggest that intake of milk has various health benefits on body such as improving bone health, lowering the risk of heart disease and diabetes, preventing sarcopenia in elders or old age, and maintains the gut health.
Infant and baby food: Milk is quite important postnatal baby food after breast milk and provide nutrients and bioactive components which enables the development of immune mechanism and symbiotic microflora in the intestine of new-borns. Milk provides energy, essential nutrients, mineral, vitamins and calcium, which help in growth and development of child especially after one year, of breast feeding. Three serving of dairy food or 350-400 ml of milk is recommended between the age of one to three years of the children.
Improved bone health: Milk and dairy foods are a very good source of protein calcium and vitamin which is essential for bone growth and development. Milk calcium is easily absorbable and digested in the body ie milk and milk products are reliable source of calcium. Regular consumption in recommended dose will help in maintaining the bone and muscle mass, and result in a long life healthy bone mass.
Blood pressure regulation and cardiovascular health: Milk contains potassium, magnesium and calcium ions which help in regulation of fluid and electrolyte balance. Potassium in particular play quite an important role in preventing heart stroke, and maintaining healthy blood pressure. American dietary guidelines have also recommended three servings of low-fat milk, yoghurt or cheese on a regular basis each day. Milk and milk products also contain some bioactive peptides which regulate the blood pressure by ACE inhibitory activity and stop the conversion of angiotensin I to angiotensin II. It has been investigated by various studies that people who include milk and dairy foods in regular diet have lower risk of cardiovascular disease and type 2 diabetes.
Improvement of gut health: Fermented dairy products and probiotic drinks have a positive impact on gut health and improves the digestive system, probiotic drink includes the live bacterial culture which aids in digestion, prevents growth of pathogenic microorganism, ie prevents the variety of intestinal diseases like IBS , inflammatory bowel disease and enhance the immune system. Probiotic drinks are quite popular drink among fitness industry. Fermented dairy products fix the problem of lactose intolerance, where lactose sugar has been metabolized by the microorganism.
Women after menopause are more prone to osteoporotic fracture because of low dietary protein and calcium intake, protein intake has been seen to be associated with calcium absorption and are associated with bone mass, women after menopause are four time more prone to osteoporosis than man, although older man are also susceptible. So, balanced diet is quite important to solve this problem, especially at older age. Researchers investigated that protein and calcium in dairy foods play a critical role in maintenance of bone density and muscle mass in elder people ie reduce the risk of osteoporosis. Studies have shown that regular intake of fat free or low-fat dairy products at least three servings a day provide essential nutrients for bone and muscle health, reduced the risk of progression of arthritis and osteoporosis in older people.
Whey protein drinks are quite popular product for bodybuilders and fitness industry, because of its bioavailability and nutritional properties. Whey protein is rich source of branched chain amino acid, which are metabolized directly into the muscle tissue. Whey protein are good source of leucine essential amino acid which promotes muscle protein synthesis and hence the muscle mass. Whey protein comprises various protein like β-lactoglobulin, α-lactalbumin, bovine serum albumin, lactoferrin and lactoperoxidase etc., which have anti-carcinogenic, immunomodulatory, and antimicrobial properties. Whey protein has been studied to improve insulin sensitivity, which lower the fat deposition.
Anticarcinogenic activity: Calcium and vitamin D are present in milk are investigated to possibly reduce the risk of colon, prostate and breast cancer in humans. Calcium protect the gut lining by oxidizing action of fatty acid and bile acid by binding and solubilizing them ie prevent direct contact with colon or rectal wall. Whereas, Vitamin D check cell growth proliferation. Vitamin D is also associated with production of serotonin hormone which effect the mood, sleep and appetite. Vitamin D fortified milk has also been produced by manufactures to achieve its health benefits.
Prevention of Tooth decay and oral hygiene: Milk and dairy products consumption are studied to lower the incidence of plaque formation and dental carries (tooth decay) by reducing the oral acidity and stimulating the saliva production.
Milk and milk products are integral part of our balanced diet regime, due to its nutritional composition and health benefits. Milk products are the prime choice of researchers these days for development of functional food, and more over fat free or lower fat dairy products are suitable for all age groups including children, adults and elder people. Fermented dairy products can also be consumed by peoples having lactose intolerance. Milk and milk products help in prevention and control of various diseases.
Dr. Dinesh Kumar *
* Veterinary Surgeon (Government of Haryana)
Dr. Rajender Kumar **
** ICAR-NDRI, Karnal, Haryana
Shailesh Kumar Meena***
***Research Scholar ICAR-NDRI, Karnal, Haryana