Should We Be Consuming Dairy?
You may have grown up being told that you should be drinking 3 glasses of milk per day or consuming 3 servings of dairy to support the growth of strong bones. Dairy is an excellent source of calcium, phosphorus, protein and is fortified with vitamin D. However, just like anything else, too much of anything can have negative consequences to our health. Let’s dive into the pro’s and con’s of a consistent dairy intake.
Studies have shown that consuming full-fat dairy and fermented dairy products can be a part of a healthy diet. Full-fat dairy can protect against metabolic syndrome, type II diabetes, and cardiovascular disease. Grass-fed dairy, when the fat is still intact, is an excellent source of fat-soluble vitamins and conjugated linoleic acid (CLA). CLA is an anti-inflammatory fat that can reduce cancer risk and improve body composition. Bonus points if you are eating fermented dairy which contains probiotics Lactobacillus and Bifidobacterium.
Cardiovascular Health
A few studies have examined the relationship between dairy intake and cardiovascular health. Within one of the studies, greater dairy food consumption was positively associated with better global cardiovascular health. Keeping diet and other lifestyle factors consistent, the individuals who had higher intakes of whole fat milk, yogurt, and cheese were associated with a better cardiovascular health score than those who consumed little to none. In a similar study, a higher intake of dairy foods, except milk, was associated with a lower cardiometabolic risk score.
Bone Health
In a recent epidemiological study, in children and post-menopausal women who consumed cow’s milk, powdered milk supplements, or whey protein had slow bone turnover rates or higher bone mineral density values. The only data to support milk consumption and increased fracture risk have been through observational studies with very conflicting results. A meta-analysis study in 2011 found no associated between milk consumption and bone fractures of the hip. There is more research to be done to determine whether the sugar, D-galactose, in milk plays any role in increasing oxidative stress thus inhibiting proper calcium uptake by the bones. Choosing fermented dairy such as cheese, yogurt and fermented whole milk have lower concentrations of D-galactose.
Optimizing adequate vitamin D and K2 levels for calcium absorption is crucial to maintain normal serum calcium and phosphorus levels to allow for bone mineralization. Without vitamin D, bones will become brittle since there is no absorption of calcium into the bone, which can increase the risk for cardiovascular disease.
The Dilemma
However, most dairy today is highly processed and stripped of it’s most beneficial nutrients. Due to pasteurization and homogenization that most cow’s milk goes through destroys many of those bioactive molecules that support growth and development. This is why choosing raw or low-heat (VAT) pasteurization dairy has a higher nutritional profile than conventional dairy.
Leaky Gut
A leaky gut occurs when the cells lining the intestinal walls become damaged. This barrier than loses its ability to regulate which molecules cross into the body. Dairy contains protease inhibitors. Protease inhibitors neutralize digestive enzymes that normally break down protein-rich food into simple amino acids. When our bodies sense that we don’t have enough digestive enzymes, the pancreas secretes even more digestive enzymes into the small intestine. This causes an imbalance of enzymes including trypsin. Too much trypsin can weaken the connection of enterocytes (cells of the intestinal lining), making it easier for connects to leak into the bloodstream. Indigested proteins that cross the enterocytes can release inflammatory cytokines which leads to inflammation.
While dairy is NOT the root cause of a leaky gut, if you are suffering from a leaky gut, dairy may not be the best option for your gut healing. First, address the gut imbalance, then you can add dairy back in to see how your body responds. You need a healthy gut to reap the benefits of ANY food you consume.
Conclusion
Ultimately, total nutritional intake and lifestyle choices are the biggest factors in achieving peak bone mass. Historically, calcium and vitamin D intake were associated with bone formation, however, we are recognizing the importance of other vital vitamins and minerals that support this process (vitamin K2, magnesium, phosphorus). There is a large majority of the population who lack the enzyme lactase to properly digest milk products after infancy. Because milk substitutes such as fortified soy and nut milks have not been around as long as milk, we can not accurately argue if they are as bioavailable as calcium from whole food sources. If you simply do not like the taste of dairy or do not tolerate it well, consuming calcium from green leafy vegetables (collard greens, kale, broccoli), sardines, salmon with bones, soybeans, tofu/tempeh, almonds, seeds.
Whether or not you want to include dairy in your diet is a completely individualized decision. For a person not suffering from an autoimmune condition or an allergy or intolerance to dairy, it can be a nutritious source of important vitamins and minerals.
I personally do not consume dairy products on a daily basis. However, I do enjoy whole milk yogurt and milk once in a while and opt for grass fed cheddar when I can! It’s a very delicious addition to meals and snacks. Life is too short to to not eat the REAL deal.
Sources:
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Lutsey PL, Michos ED. Vitamin D, calcium, and atherosclerotic risk: evidence from serum levels and supplementation studies. Curr Atheroscler Rep. 2013;15:293
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