Chances are you’ve had the benefits of dairy milk drilled into your head for years — strong bones! Good health! And while these are all good, science-backed things, it turns out there is such a thing as drinking too much milk and it could have adverse effects.
Yes, the substance we were encouraged to drink as kids is rich in calcium to help boost bone density and also acts as a great source of protein, but too much of it can cause acne, digestive issues, and may even increase your risk of developing certain cancers.
We detail the evidence-backed signs to watch for that you’re drinking too much of this dairy product. And for more on milk, find out what you need to know about how drinking milk can impact your health.
Before we delve into what too much milk can do to your body, let’s establish rough guidelines for how much milk you should be drinking per day. According to a report from the United States Department of Health and Human Services, people over the age of nine can drink three cups of milk per day. That’s based on the premise that milk and other dairy products are excellent sources of calcium, phosphorus, vitamin A, vitamin D (in products fortified with vitamin D), riboflavin, vitamin B12, protein, potassium, zinc, choline, magnesium, and selenium.
Overconsumption of milk isn’t a big issue; most Americans aren’t meeting the three-cup-a-day threshold. And that’s good news because you don’t need all of that milk in order to reap the beverage’s nutritional benefits. If you’re consuming roughly 2,000 calories a day, The National Dairy Council found that just one 8-ounce serving of milk delivers a unique nutrient package that puts you well on your way for meeting the daily value for calcium, riboflavin and other key nutrients.
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One important caveat to note with milk consumption is that there are some people who should stay away from the healthy drink altogether. This includes the estimated 30 million to 50 million American adults who are lactose intolerant. Lactose intolerance is typically caused by a deficiency of an enzyme in the body called lactase, which breaks down lactose found in milk and is essential to its complete digestion.
As your lactose-intolerant friends might tell you, drinking dairy milk with the condition is no fun. It can cause abdominal cramps, bloating, and diarrhea. If you still want to consume dairy products, but believe you have a lactose intolerance, there are plenty of dairy-based alternatives, like lactose-free milk, ultra-filtered milk, and lactose-free yogurt as well as plant-based options like milk substitutes.
Since some of the side effects of drinking too much milk are pretty common, it can be difficult to tell if the discomfort you’re feeling is directly related to your milk consumption. Here are five warning signs to look for that indicate you’ve been drinking too much milk.
You could still be sensitive to lactose without having a full-blown intolerance to it, and too much of it can cause other digestive issues, such as a “leaky gut,” which is when bacteria and toxins are able to “leak” through the intestinal wall. This can occur because, per a 2008 review of studies, protease inhibitors, which are found in bovine milk, cause digestive enzyme imbalances and overproduction of trypsin, an enzyme that destroys the connections between the intestinal cells.
Research has shown that increased milk consumption may also contribute to a “leaky gut.” The theory is that a1 casein (which is found in dairy milk) has inflammatory effects on the intestinal lining, which may increase the permeability of the gut lining. The result is something called microbiome dybiosis, where the gut bacterial microbiome is imbalanced with more bad bacteria than good. Cornell researchers recently connected leaky gut to chronic fatigue syndrome, a condition where normal exertion leads to debilitating fatigue that isn’t alleviated by rest.
(One solution, which we include in the best dairy milk brands, is opting for a2 Milk. This brand removes the a1 protein, and it may be a good substitute for those with a milk intolerance.)
When you constantly feed your body something that it can’t tolerate, it can lead to inflammation. And that inflammation will manifest itself in different ways—one of which is through your skin.
A Clinical, Cosmetic and Investigational Dermatology study found that full-fat dairy products were associated with moderate and severe acne, the odds ratio was 4.81 for boys and 1.8 for girls. A recent meta-analysis of 14 studies found that whole milk, low-fat milk, and any milk were positively associated with acne.
It’s well-known that the calcium in milk helps strengthen your bones, but because milk can also cause inflammation, there has been some research that suggests that consuming too much milk can actually make your bones brittle and more fragile. For example, a study published in The Journal of Nutrition in 2015 found that eating dairy foods increased low-grade inflammation in a small sample of German adults.
Additionally, a 2014 BMJ study found that excessive milk drinking appeared to actually increase a woman’s risk of broken bones, compared with women who drank little milk. The risk of any bone fracture increased 16 percent in women who drank three or more glasses daily, and the risk of a broken hip increased 60 percent, the findings indicated. If your doctor finds a link between milk and your bone density, you can replace milk as your primary source of calcium with these The 20 Best Calcium-Rich Foods That Aren’t Dairy.
According to an October 2014 study in The BMJ, drinking too much milk was related to an increased risk of death and in men and women as well as an increased risk of cardiovascular disease and cancer in women. More specifically, the researchers found that women who drank three glasses of milk or more every day had a nearly doubled risk of death and cardiovascular disease, and a 44 percent increased risk of cancer compared to women who drank less than one glass per day.
Men’s overall risk of death increased about 10 percent when they drank three or more glasses of milk daily.
If you experience chest pain, or have suffered from a stroke or heart attack, it may be worth asking your doctor if you should still be drinking milk. To better improve your health, consider adding these 20 Foods That Can Help Lower Your Risk of Heart Disease to your diet.