Cow’s milk is an old, popular food. It’s being used as a staple in many households since ages. Milk and Milk products have been a crucial part of the human diet for some 8,000 years and are officially recommended by apex nutritional bodies of many countries worldwide.
In recent times, few researches suggest milk may have some ill effects on various health aspects. On the other hand, there are evidences that suggest milk has multiple health benefits including preventing chronic lifestyle disorders like diabetes and heart diseases.
Complete food
Milk is a powerhouse of nutrition. It’s considered as a whole food with 18 of 22 essential nutrients present in milk. Milk is a great source of calcium, phosphorus, vitamin B12, vitamin A, iron, selenium, protein etc.
A cup (250 ml approx.) of whole milk contains 4.6 grams of saturated fat, which is about 20% of the daily amount for the Americans. Critics often say the saturated fat present in milk are harmful for the heart health. However, this criticism has been called into question basis recent experimental research showing no association between saturated fat and heart diseases. In fact, in current time, high fat ketogenic diet is producing substantial health benefits when practiced under expert guidance.
Multiple benefits
Important for bone and teeth health: A cup of milk provides almost 30% of the daily calcium needed by a healthy adult. Milk is rich in potassium and magnesium too. All these minerals are important for healthy bones and teeth. A large review assessing numerous observational studies and Randomized Control Trials (RCTs) have shown a favourable effect of dairy products on bone health during childhood and adolescence. A two-year long RCT involving 195 adolescent girls found avoiding milk was linked to increased fracture risk.
Bone fracture and milk? No solid evidence:
Recently, there are some evidences linking bone fracture or osteoporosis and milk consumption. But osteoporosis or porous bones are not always related to nutrition, hormones and exercises have a large role to play too. For example, osteoporosis is much common in women than in men post menopause.
The connection between bone fracture and milk consumption often explained by the theoretical basis for the acid-alkaline diet, which suggests choosing foods that are alkaline in nature and avoiding foods that are acid forming such as milk protein. However, there is a lack of scientific evidence supporting this hypothesis. Conversely, consistent evidences are available linking protein intake and improved bone health.
Gold standard evidence states dairy is good for bone health:
Observational studies produce mixed result. Few observational studies reported that increased dairy intake has no effects on bone health and may be harmful in long run. However, there are a greater number of observational studies stating otherwise. The data from observational studies are inconclusive and can’t be considered for universal application as they lack scientific study design.
There is a pool of well-designed RCTs, known as ‘gold standard’ of science found positive association between dairy consumption and bone health in all age groups – childhood, adolescents and adults.
Milk doesn’t cause type 2 diabetes, rather prevents it:
Multiple scientific studies have demonstrated a link between drinking milk and a reduced risk for type 2 diabetes. A review of literature found milk protein is linked to improved metabolic health. A study involving almost 82000 post-menopausal women tracked their consumption of milk products and yogurt over the period of eight years and reported a diet high in low-fat dairy products is associated with lower diabetes risk in those women, particularly those who are obese.
Another study from 2011 reported reduced risk of type 2 diabetes in adults who consumed more dairy products during their adolescence.
There is countless evidence supporting preventive effect of milk consumption in developing type 2 diabetes.
Milk doesn’t affect heart health:
Instead, whole milk fat may help raise levels of HDL (good) cholesterol that leads to prevention of heart disease and stroke as reported by a three-week randomised crossover study.
Additionally, grass-fed cow’s milk with considerable amount of omega-3 fatty acids and conjugated linoleic acid help protect heart and blood vessel health.
Connection between cancer and milk consumption is a vast area of debate.
All evidence produced so far in proving a link between cancer onset and dairy intake are observational that estimates the relationship between dietary intake and the risk of getting a disease. These studies usually discuss an association but can’t prove a cause-effect relationship. There can be multiple reason involve until proven otherwise by controlled trials. Even though, most of the studies reported reduced risk of colorectal cancer with daily consumption of dairy. Stomach cancer, the fourth most common cancer in the world found not to be associated with consumption of milk from grass-fed cows.
There is no consistent evidence either connecting dairy products with breast cancer. In fact, some types of dairy found to be protective against breast cancer. However, there are couple of evidences linked the risk of prostate cancer in men with dairy consumption.
To conclude:
Milk is a whole food enriched with several essential nutrients in an easily available form. Drinking milk is important for all age groups to borne multiple health benefits. Except lactose intolerance or allergy or any other special condition, consumption of milk and milk products are safe in recommended amount.
(Subhasree Ray, Doctoral Scholar, Clinical and Public Health Nutritionist, Certified Diabetes Educator. She can be followed on her Twitter @DrSubhasree)
