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Assortment of items containing dairy, including milk and cheese.

“Is dairy good or bad for you?” Post that question to social media and you’ll find so much debate about this food group, that you might mistake it for a political campaign.

On the pro-dairy side, you’ll see answers such as:

  • “I’ve been drinking a gallon of milk a day since I was a little kid.”
  • “It’s one of the food groups.”
  • “My dietitian told me to eat it/drink it.”
  • “I need it for strong bones.”

On the anti-dairy side, you’ll see people respond with answers like:

  • “It causes digestive problems.”
  • “Dairy causes cancer.”
  • “Humans aren’t cows and therefore shouldn’t consume cow’s milk.”
  • “It’s not fair to the cows.”
  • “It’s an animal product and animal products are bad for you.”

Ask them how they came to their conclusions and you’ll find most people don’t really know why they believe what they believe. Maybe a friend told them something. Perhaps they read an alaramist’s blog post. Maybe they saw a biased advertisement.

Like many of the polarizing topics in nutrition, the answers lie in the middle. There are actually few topics where you can generalize across the population…eliminating gluten, limiting alcohol consumption, and avoiding BPA being part of that very short list.

In this article, I’ll outline the most common concerns and exaggerations related to dairy consumption. “Dairy” is a broad category of food as well. Where it’s appropriate, I’ve differentiated between milk, cheese, whey protein, and fermented dairy.

If you’re looking for a specific topic, click on one of the shortcuts below.

4 Reasons Dairy Is Good For You

I’ll start by explaining why dairy is good for you, provided you can eat or drink it. Then, I’ll get into the reasons why it’s not for everyone.

1. Muscle Growth and Improved Body Composition

Muscle growth or maintenance is important at any age.

From a toddler developing strength and coordination so he can walk without falling over, to an elderly adult, trying to maintain strength and coordination, so he can walk without falling over, and all of the quality-of-life between those two stages of life, the more muscle you have (naturally), the better you’ll function.

That’s why I weave this statement into as many articles as I can…

Muscle is your quality-of-life savings account. The more you have as you enter old age, the longer you’ll be able to maintain your quality-of-life.

Of course, muscle doesn’t grow on its own. You need to follow a great strength training program. But then you also need to eat a high-protein diet, too. And in terms of protein quality, it’s hard to beat dairy.

Dairy contains two proteins, casein and whey. Both are high in essential amino acids, though whey tends to be tolerated better than casein.

Whey Protein

Whey protein is rich in essential amino acids, including the branched-chain amino acids leucine, isoleucine, and valine. It is also made of bioactive fractions like lactalbumin and lactoferrin.

Supplementing with whey protein may

  • decrease appetite*
  • reduce body weight and body fat*
  • improve glucose tolerance and help maintain normal blood sugar levels*
  • support normal lipid levels*
  • and stimulate protein synthesis better than consumption of other protein sources.*

In one study, participants were simply instructed to add whey protein to their normal diet, and not change anything else. They lost weight, reduced their waist size, and improved body composition.

Whey protein is easy to digest and absorb, and mixes well in food and beverages, which is why it’s the main ingredient in high-quality health foods like Life Time Grass-Fed Whey Protein and Halo Top ice cream.




Casein is the other protein in dairy. When you think of cottage cheese, the liquid is whey protein, the solid curds are the casein.

Casein is also rich in essential amino acids, but is digested differently from whey. It takes longer to break down, and unfortunately, is more likely to cause an allergic response in people.

Between the two protein sources, whey has considerably more research supporting its health benefits, but casein fits in well with a healthy diet too, especially since it’s the main protein in cottage cheese and Greek yogurt.

Dairy Food or Supplements for Muscle Growth?

I steer people toward food as much as possible over resorting to supplements. But when it comes to dairy, it gets harder to digest milk and cheese as you get older, which I’ll address below.

It’s also easy to add whey protein to other foods, or mix it into a shake to accompany a meal. If there was one type of dairy food to include in your diet, it’s hard to argue against the plethora of research supporting the use of whey protein.

With that in mind, as long as you tolerate whey, it’s a good idea to have a bottle of whey protein powder in your cupboard to support your high-protein diet. Just stay away from the artificially-sweetened, carageenan-filled junk you find on most retail shelves.

2. Heart Health

Since the 1960s, when we were first told that dietary fat causes heart disease, we’ve been warned about eating high-fat dairy. The theory was that the fatty acids and cholesterol would cause atherosclerosis.

What happens when policies are created based on theories instead of facts and experience? They’re often wrong. Such is the case with high-fat dairy and heart health.

Multiple studies show no connection between full-fat dairy consumption, and heart disease. Some studies even suggest full-fat dairy could lower heart disease risk.

Consumption of fermented dairy products is associated with:

  • lower LDL cholesterol
  • improved blood pressure
  • reduced risk of cardiovascular disease
  • fewer deaths from cardiovascular disease

Of course, it’s possible these associations are the result of other healthy lifestyle choices practiced by people who consume dairy. For example, one study showed that children who ate more than 60 grams of yogurt per day tended to have a higher quality diet in general.

As I mentioned above, whey specifically has been shown to improve lipid and glucose level as well, which could reduce the risk of cardiovascular disease.

One other way dairy may be cardioprotective is through its effect on uric acid levels.

High uric acid levels increase the risk of cardiovascular disease. Dairy consumption lowers plasma levels.

You might double down on the uric acid effect by combining dairy and coffee. Coffee also may lower uric acid. Another reason coffee is good for you. (For more on uric acid, see “Uric Acid: A New Metric for Heart Health.”)

So, all-in-all, the research shows higher dairy intakes may reduce the risk of death from cardiovascular disease.

3. Convenience

Let’s face it…eating well isn’t always convenient. When I stop at a gas station during a road trip, there are two main options. Jerky or protein bars. While I normally avoid nitrates found in jerky, and artificial sweeteners found in Quest Bars, either is a better option than most anything else at the gas station. I’ll often grab both.

4. Enhanced Immune Function

Dairy also contains other immune system-supporting protein fractions, including

  • immunoglobulins
  • transforming growth factor
  • lactoferrin
  • antimicrobial proteins
  • oligosaccharides
  • interleukin-10

These are just some of the findings from milk and its protein fractions:

  • Farm milk consumption is associated with fewer allergies
  • Whole milk consumption is associated with reduced frequency of diarrhea in children
  • Colostrum consumption leads to reduced frequency of respiratory infections and fewer cases of the flu
  • Immunoglobulins can bind to bacteria, viruses and inhaled allergens, and have been shown to improve stool consistency in children
  • Transforming growth factor beta is anti-inflammatory, and also helps improve the barrier function of the intestine
  • Lactoferrin acts as an antimicrobial compound, inhibiting iron-dependent pathogens

With these immune-supporting benefits in mind, milk might be one of the most important foods for young, picky eaters.

8 Reasons Dairy Might Not Be Good For You

As good as dairy can be for you, it’s not right for everyone. Some people don’t do well with certain types and others need to stay away from dairy altogether.

That said, just because you might be among those who don’t handle dairy well, it doesn’t mean everyone should avoid it.

1. Lactose Intolerance

Lactose is milk sugar. To digest it, you need the enzyme lactase, which breaks lactose down to glucose and galactose. Without sufficient lactase, people develop lactose intolerance.

The most common symptoms of lactose intolerance include abdominal pain, gurgling in your stomach, constipation, diarrhea, gas, and vomiting. However, some people may also experience headaches, memory loss, muscle and joint pain, and other allergic reactions.

Lactose intolerance is pretty common. It has one of the following four causes.

  1. Congenital lactase deficiency. This genetic cause begins with birth and persists through life. Most cases are found in Finland. Breast-feeding causes watery diarrhea. Through careful diet strategies, babies born with this genetic anomaly can live a normal life today.
  2. Developmental lactase deficiency. Babies born prematurely haven’t developed the normal ability to produce the lactase enzyme. Though they might have trouble starting out, most of the time these babies develop the ability to digest dairy, or more specifically, breast milk.
  3. Primary lactase deficiency or adult hypolactasia. This is the most common cause of lactose intolerance. As humans mature, they lose the ability to break down lactose. Though they don’t lose 100% of the enzyme activity, between the age of 30-40, they lose most of it, which is when symptoms of lactose intolerance first appear.
  4. Secondary lactase deficiency. Secondary lactase deficiency occurs as the result of another disease or digestive complication, such as coeliac disease, Crohn’s, or malnutrition. Often, once the primary dysfunction gets resolved, the lactose intolerance disappears.

Does lactase supplementation help with lactose intolerance?

For those with lactose intolerance, it isn’t always possible to completely avoid lactose. Milk sugar can find its way into all sorts of foods, especially when you’re eating out.

Like other digestive enzymes, you can supplement with lactase, which can reduce the effects of occasional lactose consumption. However, supplementation doesn’t allow you to break down all of the lactose you eat, especially if you go for a whole pint of ice cream or drink a gallon of milk a day.

Lactose and Vitamin D Supplements

Vitamin D is an extremely small compound. To make it easier to handle, raw material suppliers and supplement manufacturers dilute vitamin D.

Most raw material suppliers dilute their vitamin D in lactose, and then send it to the supplement manufacturer, which is then added to supplement formulas.

The way labeling laws work, the raw material manufacturer does not need to include lactose on the label sent to the manufacturer, and the manufacturer does not include it on the bottle of the finished product.

Unfortunately, many people who avoid lactose but supplement with vitamin D end up scratching their head, wondering why they still have symptoms of lactose intolerance.

This is one of the many ways we take Life Time’s nutritional products to another level. We ensure the raw materials for the Life Time Vitamin D+K, or the vitamin D used in any of our other products, is not diluted with lactose.

In terms of dairy foods, if lactose intolerance is the only issue, certain dairy foods such as heavy cream, whey protein isolate, or aged cheese can be well-tolerated. You can even find lactose-free milk and ice cream.

In the end, lactose intolerance is pretty easy to deal with. Some of the other effects mentioned below are not so easy.

2. Biogenic Amines

Biogenic amines are nitrogenous compounds produced by animals and plants. At normal levels, they do no harm. But when levels rise from consuming them in excess, or due to a compromised detoxification system, they can create serious problems.

When biogenic amine levels get excessive, they can cause any of the following symptoms.

Symptoms of Biogenic Amine Toxicity

Fermented foods are high in biogenic amines. Cheese, wine, and chocolate are three of the most common dietary sources. It’s kind of funny that those three items are a common combination at dinner parties.

Cheese is the most common cause of biogenic amine poisoning. It contains histamine, tyramine, putrescine, and cadaverine.

The highest levels of biogenic amines have been measured in acid curd cheese, washed rind cheese, blue cheese, and hard cheese. However, BAs are found in most cheese.

Because the impact of biogenic amines is a relatively new issue, only a small percentage of cheese has been tested to identify the concentration of BAs. Based on the small amount of research so far, this is what is known:

  • Not all cheese has detectable levels of BAs
  • BAs can be detected in raw milk cheese as well as pasteurized cheese
  • BAs can be detected in some cow’s milk, sheep’s milk, and goat’s milk cheese
  • Aged cheese has the highest concentrations of BAs
  • BAs are also found in yogurt and kefir, though at lower levels
  • Other dairy foods, such as milk or whey protein has negligible levels of BAs

BAs (biogenic amines) can demonstrate serious impacts on consumers’ health (e.g. release of adrenaline and noradrenaline, provoking gastric acid secretion, increased cardiac output, migraine, tachycardia, high blood pressure).

Lorencová E, et al.

3. A1 Casein

As Little Miss Muffet sat on her tuffet, eating her curds and whey, she was really eating the two proteins found in dairy: casein and whey.

Depending on where a dairy cow comes from, it will produce two different types of casein: A1 or A2 beta-casein. The difference between the two is A1 contains histidine and A2 contains proline at a specific point in the casein amino acid structure.

You wouldn’t notice a difference between the two forms of casein when consuming it, but you very well might notice a difference in how you feel after eating it.

Most western dairy has a combination of the two forms of casein, whereas cattle from Asia and Africa produce only A2. Goat, sheep, and buffalo milk do not contain A1 casein either.

When A1 beta-casein gets digested, it releases an opioid peptide called beta-casomorphin-7. Beta-casomorphin-7 is a compound akin to morphine. It has the following effects on the body.

Effects of Beta-Casomorphin-7

The morphine-like effects from casomorphin make you wonder if it’s really possible some people could be addicted to diary.

A1 dairy increases inflammation in some animals and in some (but clearly not all) humans as well.

With all that said, I don’t want to sound like an alarmist. Not everyone responds to A1 casein like this. However, if you experience some of the symptoms above, you might be among those who do.

4. Hormone Imbalance

In addition to protein, carbs, fat and micronutrients, dairy also contains hormones.

Insulin-Like Growth Factor

Dairy contains insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-2. Dairy cows treated with recombinant growth hormone to increase milk production can produce milk with even higher-than-normal levels of these hormones.

IGF-1 isn’t bad. It is the active form of growth hormone, and helps accelerate cell growth. This is a good thing for a growing child, or an adult who’s building muscle or recovering from an injury.

Depending on how much you drink, milk can increase IGF-1 by 20-30% in children and 10-20% in adults.

The increase in IGF-1 is controversial when looking at cancer, though.

Cancer cells may grow faster in a higher-IGF-1 environment. That said, IGF-1 does not cause cancer, and neither does consuming dairy. At least that’s the case based on the most current research. If you have cancer, it wouldn’t hurt to avoid dairy in your diet.


Dairy also contains estrogen metabolites, which could upset the balance of sex hormones in men and women. When estrogen gets too high relative to testosterone, you can develop symptoms of low testosterone.

Sex hormone imbalance can even lead to early menopause in women.

Low-fat, but not full-fat dairy consumption is associated with early menopause. If there is a connection, it’s believed that the concentration of estrogen metabolites in low-fat dairy may be to blame.

The strange part of this finding is that full-fat milk is higher in estrogens than skim or low-fat milk. Researchers found that when postmenopausal women consumed one liter of cow’s milk for four days, urinary excretion of estrogen increased.

Since elevated estrogen may increase the growth of certain cancers, such as breast cancer, this is something for women to be aware of. That said, one liter a day of milk is a lot of milk for an adult.

Women with polycystic ovary syndrome or men with low testosterone should probably stay away from milk and cheese.

A glass of milk on occasion isn’t going to cause moobs in men or estrogen dominance in women. But an excessive amount every day might lead to problems in some people.

5. Digestive Problems

Does dairy cause digestive problems? Not likely. Protein fractions, like those I mentioned above in the section on immune function, actually enhance the function of the gut.

However, some people do have dairy allergies. Others have lactose intolerance. And still others may have a dysfunctional gut from other diet, medication, and lifestyle choices.

When you consume dairy and already have digestive problems, it’s possible the dairy can make things worse. The worse the digestive issues, the more of a problem dairy might cause. Ulcerative colitis is a good example.

Ulcerative colitis is at about the extreme of a dysfunctional gut.

Though dairy probably doesn’t cause colitis, it definitely increases the risk of flare ups. Also, since those with colitis are more likely to have leaky gut, they’re more likely to develop sensitivities or allergies to milk, as the milk particles are more likely to reach the circulation.

This is why going dairy-free is often recommended as part of a gut-restoring protocol, or when following an elimination diet.

I’ll round out this list with a few more negatives about dairy consumption to consider. There isn’t a significant amount of research supporting these issues, but there’s enough anecdotal evidence they shouldn’t be dismissed either.

6. Arthritis

I don’t believe dairy consumption causes arthritis. But it’s possible that it could make the problem worse when someone has it. Take this case study from almost 40 years ago as an example.

A 38-year-old woman, and mother of three had suffered from erosive seronegative rheumatoid arthritis since the age of 27.

Multiple medications failed to provide relief or limit the progression of the disease. She’d progressively developed allergies to many medications and dealt with repeated digestive problems.

She loved cheese, and ate up to a pound of it in a day. Though she had not allergic symptoms from dairy, her doctor convinced her to eliminate all dairy products for a while.

Within three weeks, her symptoms improved. However, they’d return within about 12 hours of consuming dairy, even when it was in small amounts and accidental. Eventually, her health improved and she was able to stop taking prednisone.

British Medical Journal Case Study, 1981

You might think, “I’d never eat a pound of cheese, so this doesn’t apply to me.” The thing is, when your body reacts to a food, the dose doesn’t matter. Just a tiny amount a couple times per month could keep you feeling the symptoms.

So, if you have arthritis, it wouldn’t hurt to “cut the cheese” for a while and see what happens.

7. Sinus Congestion

If you talk to a handful of people, you’ll find someone who notices their sinuses clog up, or that they get phlegm stuck in their throat after consuming dairy.

Most of the standard medical sites refute that this could happen. It’s just an example of medical references needing to catch up with reality.

Studies that have looked at whether dairy causes mucus production haven’t shown much. However, in studies where people complained of excess mucus production, removing dairy from the diet reduced mucus production.

One theory is that in those with increased intestinal permeability (leaky gut), some of the milk particles enter the circulation and trigger an immune response, which includes an increase in mucous production. Again, this is just a working theory, though.

8. Skin

A small amount of evidence points to fermented dairy playing a role in improved skin health. It’s unknown whether it’s the dairy itself, or the probiotics found in fermented dairy like kefir and yogurt.

However, heavy milk consumption, especially in men, is a common trigger of acne.

There’s even some evidence that whey protein could trigger acne outbreaks in some people.

Thought the connection is well-known, the cause remains a mystery. Acne is an inflammatory skin condition, and since A1 casein can be pro-inflammatory, that could be part of the problem. But then again, some people seem to break out from whey as well, which is not pro-inflammatory.

3 Myths About Dairy And Health

Before wrapping this up, I need to address three myths about dairy that continue to be repeated, even though the research doesn’t back them up.

Myth 1: Dairy Causes Cancer

Alarmists say that dairy increases the risk of cancer. Most of the hysteria surrounding dairy and cancer comes from T. Colin Campbell’s research. Campbell fed rats a diet of casein protein.

He found that the casein-fed rats were more likely to develop liver cancer than the rats that weren’t fed casein. In the real world, rats don’t milk cows, and then separate the curds and whey before dinner. That’s not their natural diet.

It would be like researching the effects of feeding chocolate to dogs (which can kill them, if you didn’t know), and then concluding that chocolate is lethal for humans.

One other connection to cancer is dairy’s impact on insulin-like growth factor-1 (IGF-1). IGF-1 is a marker for growth hormone levels.

Cancer cells exposed to IGF-1 can grow faster, but that doesn’t mean increasing IGF-1 causes cancer. It’s critical for growth and repair throughout life.

In addition, fermented dairy is associated with reduced cancer risk.

In the present meta-analysis, which included 61 studies with more than 1.9 million participants and more than 38,000 cancer cases, statistical evidence supported an association between fermented dairy food intake and overall decrease in cancer risk.

Zhang, et al.

However, Downer, et al (see references) did find an association between full-fat dairy consumption and advanced stage prostate cancer. The study group included only 525 people, though, so the power of that study compared to the one I highlighted above is miniscule.

Myth 2: Dairy Enhances Bone Health

If you were to ask the average person what the number one benefit of dairy is, you’d likely be told that it’s important for bone health. It’s been sold that way for decades.

Yet, according to the research, there’s no difference in bone health or fracture risk between those consuming low amounts of dairy and those consuming high amounts

In elderly women, there is an association between higher dairy consumption and bone density, but you can’t say it’s the dairy that improved the bone density. It could be the higher protein intakes, higher levels of activity, better overall diet, or some other factor from women who consumed it. 

Milk isn’t actually a good source of calcium. And calcium alone won’t help you maintain bone health. If you’re in middle or older adulthood, hoping to preserve your bone mass by drinking milk, that’s probably a lost hope.

You’re better off eating a high-protein diet, committing to a great strength training program, and supplementing with magnesium and vitamin D, all of which have been shown to support or enhance bone density.

So, you can get your calcium, magnesium, vitamin D, and protein from other sources and be just fine. This is just another example of marketing over science.

Myth 3: Dairy Causes Diabetes And Obesity

Full-fat dairy is high in total fat and saturated fat, so it makes you fat, right? Wrong. Well, at least it doesn’t make you fat if you’re not overeating carbs.

In population-based research, as dairy consumption increases, the risk of metabolic syndrome and diabetes decreases. That’s contrary to the myth that dairy can cause diabetes.

Dairy does increase insulin, as most protein sources do. Insulin increases amino acid uptake. But just because insulin increases, it doesn’t mean dairy causes pre-diabetes and diabetes.

In fact, whey protein, which increases insulin, actually improves insulin sensitivity, blood sugar, and insulin levels.

So, dairy won’t turn you into a cream puff alone. It’s more likely that the cookies cause the weight gain, than the milk you dunk them in.


So what’s the punch line? Should you eat dairy, or avoid it? I can’t offer a specific “yes” or “no” like you see from so many extremists. What I can suggest is this:

  • If you tolerate dairy, and don’t experience any side effects go for it. I’d strongly encourage you to use a high-quality whey protein powder as part of your nutrition plan. And when you’re craving dessert, get some Halo Top or Enlightened ice cream.
  • If you experience some of the symptoms above, or already have a compromised digestive system, limit or eliminate dairy and see how you do.
  • If you have a hard time getting enough protein from food alone (between 0.8 and 1.0 grams per pound ideal body weight per day), use a high-quality whey protein powder. As mentioned above, whey is one of the best, if not the best source of protein you can consume.

With all that said, I hope this will help you ignore that one friend who has a cow each time you sit on your tuffet, and eat your curds and whey.

On the flip-side, you can tell your friend from the dairy industry, “Milk doesn’t always do a body good.”


Keep the conversation going.

Leave a comment, ask a question, or see what others are talking about in the Life Time Health Facebook group.

The Life Time Health Team

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