Dairy: Health food or health risk?

Matthew Solan

Executive Editor, Harvard Men's Health Watch

When I was a growing teenager, I drank as much milk as possible (often straight from the carton while standing in front of the open fridge, much to my mother’s chagrin). I’d seen the TV ads — milk and other dairy foods were the express ticket to stronger bones and bigger muscles.

But today dairy’s nutritional reputation is as clear as, well, a glass of milk. Dairy is either good or bad for you depending on the latest diet trend or recent study. So what is the truth — is dairy healthy, or a health risk? “Dairy isn’t necessary in the diet for optimal health, but for many people, it is the easiest way to get the calcium, vitamin D, and protein they need to keep their heart, muscles, and bones healthy and functioning properly,” says Vasanti Malik, nutrition research scientist with the Harvard T.H. Chan School of Public Health.

Dairy products as a source of calcium and protein

Dairy products like milk, yogurt, cheese, and cottage cheese, are good sources of calcium, which helps maintain bone density and reduces the risk of fractures. Adults up to age 50 need 1,000 milligrams (mg) of calcium per day. Women older than 50 and men older than 70 need 1,200 mg. (For comparison, a cup of milk has 250 mg to 350 mg of calcium, depending on the brand and whether it’s whole, low-fat, or nonfat. A typical serving of yogurt has about 187 mg of calcium.) Milk is also fortified with vitamin D, which bones need to maintain bone mass.

Older adults also need protein to protect against sarcopenia, the natural age-related loss of muscle mass and strength, and dairy can be a decent source. The recommended amount for older adults is 0.8 grams per kilogram of body weight. A 180-pound man would need about 65 grams of protein per day, and a 140-pound woman would need about 50 grams.

Still, when it comes to the direct health impact of dairy, the existing science is mixed. Some research warns against consuming too much dairy, while other studies show some benefits from regular dairy consumption.

Is one form of dairy better than another?

The American Heart Association still recommends adults stick to fat-free or low-fat dairy products. But new research suggests full-fat dairy might not be much of a threat to heart health. A report presented at the 2018 Congress of the European Society of Cardiology looked at 20 studies involving almost 25,000 people, and found no association between the consumption of most dairy products and cardiovascular disease. The exception was milk, but the results showed that only very high milk consumption — an average of almost a liter a day — was linked with a higher risk of cardiovascular disease.

Some science has even suggested that the right kind of dairy may prevent heart disease. A study involving 2,000 men published by the British Journal of Nutrition found that those who ate plenty of fermented dairy products like yogurt and cheese had a smaller risk of coronary artery disease than men who ate less of these products. This supports earlier studies that showed that fermented dairy products have more healthful effects on blood lipid profiles and the risk of heart disease than other dairy products.

Another proposed benefit, however, has not panned out. “Despite the push by the US dairy industry to promote dairy products, especially milk, as a weight-loss tool, research hasn’t supported that except when also restricting calories,” says Malik.

The bottom line

When it comes to overall health benefits, it seems that dairy is neither a hero nor a villain. Adding some dairy to your daily diet — a splash of milk in your coffee or a cup poured over your breakfast cereal, or a slice of cheese on a sandwich — can help you get some of the vital nutrients you need. “But keep in mind that eating a well-balanced diet that includes plenty of green leafy vegetables and nuts can better help you get the calcium and protein you need rather than relying too much on dairy,” says Malik.

Malik still prefers most people stick with low-fat dairy, as this helps reduce your intake of saturated fat but still offers good amounts of nutrients. Alternatively, you can choose almond and soy milk substitutes — but be aware that they have lower amounts of protein than regular milk. For a single go-to dairy source, Malik recommends plain Greek yogurt. (Avoid flavored versions, which are high in sugar). “It has more protein than regular yogurt and contains probiotics that help with gut health. And it’s quite versatile, as you can eat it alone or add it to other dishes like smoothies and use it as a substitute for cream in recipes.”


  1. Anita

    After reading the Article on dairy, which stated that it is a good source of protein, I began to wonder if the article was complete. I learned that
    dairy products create an acidic environment in your digestive system. To counteract and neutralize this environment, calcium is leached from your bones. Thus, dairy is not a good source of calcium, rather it actually robs your body of calcium.

    • Patrick

      Can you please tell us where you learnt this?

      The article is reporting (not saying they are right or wrong, just reporting) on findings presented at medical science conferences.

      It provides details of the conferences and the studies; e.g. the British Journal or Nutrition, or a review of 20 studies involving 25,000 people.

      Since people have been advised to consume dairy products as a source of calcium, can you please provide citations for peer-reviewed scientific studies that show that dairy creates an acidic environment, and that calcium is leached from the bones?

  2. Cyrus

    So it’s ok to stick to the normal amount of milk that we all have in our tea, coffee, yoghurt. But limit it in the form of cheese,butter. Moderation is the key. All said, “Dairy is good for health!”

  3. Marco Bellacci

    ” but be aware that they have lower amounts of protein”

    Well… Last time I looked it up soy milk contained even more protein than cow milk!

  4. P.M.Saleem

    You have discussed herein about heart health only. What about Kidneys ? What’s the impact of regular dairy consumption on kidneys ? A detailed discussion on this topic is necessary owing to the huge no. of people concerned about kidney health.

  5. Sergio

    what about cottage cheese and mozzarella? are these healthy options of dairy food?

  6. Cecilia

    Not easy being a parent these days! So many conflicting studies on foods!

  7. Myriam

    Dairy is one of the most inflammatory food groups. The only way it provides any health benefits if it’s raw or fermented. Functional Medicine tip.

  8. cece

    given what you have just said about dairy, I am cancelling my subscription. You obviously have much to learn.

  9. Helen Thomas

    1200 mg of calcium a day for over 70 -year-olds sounds like a lot. One cup of milk a day only provides a quarter of that amount. Apart from yoghurt, Malik recommends “a well-balanced diet that includes plenty of green leafy vegetables and nuts”. How much calcium do you get from that diet, and what are the sources?

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