Dairy Consumption - What does the research actually tell us?

There is a long standing practice for the food industry to preach the perceived benefits of dairy consumption to consumers.  It’s a lucrative industry, but one that is slowly coming under scrutiny by informed members of the public who refuse to take everything they are told at face value.  We are seeing a steady rise in the availability of dairy alternatives, particularly non-dairy milks, such as almond, rice, oat, coconut and hemp milks, and this is set to continue.  But from a scientific point of view, what does the research actually tell us?

Well for a start, the first thing to consider is why exactly so many people are considered ‘lactose intolerant’ these days and what exactly does this mean? The food we consume needs to be broken down to the smallest possible form in order to be digested by the body, and for sugars, this means single molecules known as monosaccharides.  Lactose is a disaccharide (two sugars), and lactose intolerance occurs where there is a failure of the body to break this down to a digestible form.  A specific enzyme (a digestive tool) in our bodies, known as lactase is responsible for this action, and biologically this should no longer function past childhood weaning from breastmilk (or alternatives) anyway.  Where the lactase enzyme does continue to function past weaning, it is known as Lactase Persistence, and only about 35% of the population maintains this.  Therefore, the remaining 65% will lose the ability to break down these sugars, resulting in lactose intolerance.  This is normal, and in countries such as China and Japan, where very little, if any, milk is consumed in adulthood, there is no issue.  However, in our Westernised diet, where we are increasingly reliant on milk and milk products, this is going to cause health issues, the least of which is abdominal discomfort. 

Campaigns promoting dairy consumption have tried to focus on health benefits that could be attributed to its intake.  One such example is the use of yogurt to treat diarrhea.  There are some studies which do show improvements in diarrhea with yogurt due to the cultures included, but more specific studies have in fact countered this by showing heightened benefits from treating diarrhea with cooked green plant-based diets, both in terms of the costs and the duration in which improvements in health were witnessed.  A World Health Organisation study, in fact, showed that patients suffering from diarrhea actually responded best to lactose exclusion.

Then we have the argument that dairy products are a cost effective method of including nutrients in the diet.  There is a method of measuring nutrient concentration in food, and it’s known as the ‘nutrient density score’.  So whilst dairy apparently has a good nutrient density score, fruit and vegetables, not surprisingly, provide the greatest nutrient density overall.  Grains and starches are similar to milk in their quality-to-price ratio and studies have shown that including cheap starches in the diet make it possible to fulfill all nutritional requirements by spending more on high-cost, nutrient-dense fruits and vegetables. 

Calcium always receives the greatest amount of attention when it comes to dairy consumption, but the truth is that calcium is found in soil, and is then absorbed by the roots of plants.  So grass fed cows will get a lot of calcium from the grass, but we can get all the absorbable calcium we need from plant foods too.  Think dark green leafy vegetables, such as spinach and kale! Seeds are good sources too, particularly sesame seeds. 

When it comes to the scientific research into the benefits of dairy consumption, the evidence is mixed (that’s putting it politely) and in fact, there is substantial research to show that other foods are more beneficial.  Countries with the highest dairy consumption also have the greatest incidence of osteoporosis, and the research shows that plant-based diets can reduce the risk of cancer, aid calcium transport and protein synthesis, amongst others. 

Just some food for thought the next time you go to put milk in your tea – try it without or opt instead for the dairy alternatives?  You might actually like them!