“Milk blunts fat burning. Don’t take it before exercise.”
“Chocolate milk is the ‘best sports drink’ out there and it will improve recovery.”
“Milk is bad for you and will cause cancer.”
“Milk is healthy and can aid fat loss, but it must be low fat.”
With all these confusing claims and more out there, it’s no surprise if you’re baffled about milk and dairy. Research outcomes are similarly inconsistent and confusing. Here’s the short version of what you need to know:
- People who are overweight, diabetic, or sedentary should consider restricting milk because it produces a large insulin release that is greater than expected and may worsen metabolic health in people who are already insulin resistant.
- If you are lean, insulin sensitive, and active, milk is probably not going to cause you metabolic problems.
- Whey protein, which is made from milk, is the best protein source for building muscle and improving body composition with strength training because it consistently produces superior outcomes than casein or soy.
- Whey is also very insulinogenic, however, studies suggest consuming it regularly improves insulin sensitivity in lean and overweight people. Note that we’re talking about whey protein, not milk.
- Whey protein is even being tested in studies as a therapeutic protein to help improve metabolic health (including in diabetics) and reduce body fat.
- Casein, another milk protein, has a lower digestive rate than whey, which is considered inferior if the goal is putting on muscle with training. Many people find they are intolerant of casein.
- Chocolate milk has been recommended as a useful “sports” drink for accelerating recovery due to the sugar (for carbs) and protein content. However, a lot of chocolate milk on the market contains high-fructose corn syrup and artificial chemicals, which are best avoided if the goal is recovery or body composition.
- Many people are allergic to lactose, which is in milk, and need to avoid it. In addition, some people find they are intolerant of milk (an immune reaction that is less intense than an allergy). They feel better avoiding it.
The rest of this article will give you the why behind these take away points and look at the pros and cons of milk and dairy when trying to get lean and shredded.
#1: Milk protein is very insulinogenic, meaning it leads to a large insulin release.
A study that compared the metabolic response to whey protein, cheese, cod, white bread, and wheat gluten found that the whey protein produced the highest insulin response followed by cheese and milk, with the other foods bringing up the rear.
Interestingly, the blood sugar increase was lowest with the whey and milk, whereas the bread produced the biggest blood sugar spike. Researchers didn’t know why this happened, but they think it has to do with the combination of amino acids and bioactive peptides in the milk.
So, we know milk and whey are really insulinogenic, but does it matter?
Longer term studies on whey protein supplementation suggest that taking it without excess carbohydrates thrown into the mix is beneficial and will lead to lower blood sugar and better insulin sensitivity in the long run.
For example, whey supplementation has also been found to lead to fat loss in the absence of exercise in overweight men. Insulin levels were lower by the end of the study and the men reported feeling less hungry when taking the whey protein.
Milk, on the other hand, was found to produce insulin resistance in children who were given either lean beef or skim milk. It’s been suggested that “modified” milk, as in non-fat versions rather than whole milk, is what’s causing the metabolic problems.
Association studies are inconsistent on the effect of milk intake and insulin resistance, but there is evidence that people who eat more dairy, especially yogurt, have lower diabetes risk.
If you are sedentary and/or overweight and/or insulin resistant, you should avoid milk because your metabolism is deranged (it doesn’t work right). The body doesn’t process certain amino acids (the BCAAs) properly. Plus, when you are overweight and insulin resistant your body is unable to mobilize and burn body fat effectively.
Based on the evidence, none of these problems are helped by consuming milk.
Lean, active people who are fairly insulin sensitive probably won’t degrade metabolic health by drinking milk. However, because of how it affects insulin, it’s best avoided before training…
#2: Drinking milk before training may cause sluggishness.
Anecdotal reports suggest that drinking milk before training makes people feel sluggish or low energy. This is likely due to the insulin spike it causes.
We’ve also reported in previous posts that drinking milk pre-workout may reduce fat burning. This came from a review that found that consuming milk before exercise reduced fat burning. However, a mixed meal was used and performance was not compromised. Therefore, it’s probably not something to worry about if you are metabolically healthy.
Bottom Line: You don’t need us to tell you that if milk makes you feel sluggish, don’t drink it!
If you feel energized and your performance improves with milk consumption, it’s unlikely to be a problem.
#3: Whole milk and full-fat dairy may be healthier than non-fat versions.
Research has found that people who eat more whole dairy are leaner. This association in conjunction with the fact that whole dairy provides the vitamins A, D, and K2 in a bioavailable form has led mainstream nutrition leaders, such as Walter Willett of the Harvard School of Public Health, to argue that there is little data to support the idea that reduced-fat milk leads to better health than whole milk.
Compared to whole dairy, reduced fat dairy increases circulating triglycerides, doesn’t lower calorie intake, and often has added sugar. Plus, there’s the insulin issue. It’s thought that when the fat is removed from dairy, it negatively affects metabolic health.
Bottom Line: If you drink milk, opt for whole-fat versions.
#4: Organic, pasture-raised milk is worth the money.
Whereas organic produce isn’t necessarily more nutritious than conventional, organic dairy products are: They contain higher levels of all three omega-3 fats (EPA, DHA, and ALA), more CLA, and more vitamin E and A than the conventional counterpart.
Even more important, with organic milk, you’re not getting the added growth hormones and antibiotics that are present in conventional dairy.
Besides the extra nutrition, it’s pretty darn important to avoid consuming needless antibiotics and extra hormones if you want to be lean and metabolically healthy.
#5: Milk consumption has been associated with cancer.
Milk promotes growth. It’s abundantly nutritious, which is why it’s the first food infant mammals consume.
Whether milk promotes the growth of cancer cells is unclear, but a review by Paleo researcher Loren Cordain argues that consuming cow milk proteins during developmental stages triggers the mTOR pathway and increases IGF-1, which may result in the development of prostate cancer in adulthood.
Surely you’ve heard of mTOR and IGF-1 as being “good” for building muscle, which is true. The thing is that they promote growth in general in whichever tissues they come in contact with. So, in the case of cancer, you want them reduced, whereas for muscle growth, you want them stimulated.
In addition, Mark Sisson and Chris Masterjohn point out in separate reviews of the issue that milk proteins mostly appear problematic when the fat is removed. This may be due to the elimination of the cancer-fighting CLA, which, if present, could counteract other pro-cancer elements in milk.
Things get further muddled by the fact that whey protein may inhibit cancer tumor growth due to the fact that whey raises the most powerful internally produced antioxidant, glutathione.
The evidence is inconsistent, but if you’re worried about cancer, avoiding milk protein, especially lower fat versions is indicated.
#6: The best dairy products are raw, fermented, and/or casein-free.
Compared to butter, cream, and fermented dairy such as yogurt, milk is simply a loser when it comes to taste and nutrition.
Real butter and cream are minimally processed foods that provide good fats, are low in lactose and casein, and are extremely delicious. If you get them from grass-fed animals they provide the beneficial bone-building nutrients in a form the body can use (vitamins A, D, and K).
Fermented dairy includes yogurt, cheese, cultured butter and buttermilk, clotted milk, kefir, and Indian Lassi. These are all traditional foods in many disease-free cultures. They provide beneficial bacteria for the gut and are low in lactose.
Raw dairy provides enzymes and nutrients not present in pasteurized diary. Raw dairy was standard in the U.S. until the Industrial Revolution and it’s still widely consumed in other parts of the world.
“Raw” means that it has not been pasteurized or heated to kill pathogens. Surely, if you consume dairy, you want to be sure your getting it from a safe source (produced hygienically, which is not something that factory farms are exactly “good” at).
Enjoy fermented dairy, butter, and cream to your liking because they provide health-promoting nutrients when eaten sensibly. They also provide variety and flavor for unique meals. Lastly, raw dairy is probably the “healthiest” bet as long as it’s free of disease.