There’s a lot of debate surrounding cow’s milk.
Some say don’t drink it, it’s poison.
Others are strong proponents of the white stuff to help with weight, muscle, and bone maintenance.
Because this dispute causes a lot of confusion, let's take a closer look so that you can make an informed decision.
Do added hormones in cow's milk cause health issues?
To help boost milk production, some farmers inject cows with engineered hormones called rBGH and rBST.
There are theories that these extra hormones are causing girls to go through puberty earlier. However, the concentration of growth hormones found in cow's milk is relatively small and may not be enough to impact early maturation.
Of course, it likely also depends on how much dairy you consume each day.
In terms of prostate cancer and estrogen-positive breast cancer, the majority of studies have indicated there may be a link between dairy and these particular diseases. While some hypothesize that the increased cancer risk could be from added hormones, there are no studies that show this specific link. The correlation could in fact be from a different property within cow's milk.
The good news…
Nowadays, not as many companies use engineered hormones in their herds.
To be sure, look for a product labeled "rBST-Free" or "rBGH-Free". You can also choose organic, which does not allow added hormones.
But it's important to note that all cow's milk naturally contains small amounts of bovine growth hormone, so we can't get away from it completely.
Is fat-free milk better than whole milk?
It's still up for debate.
Past research has linked saturated fat with heart disease. However, new research is bringing this assumption under fire, indicating that high-fat dairy is not linked with cardiovascular disease.
With that said, heart disease is still more firmly linked to a higher intake of saturated fat from red meat.
So there does seem to be something going on with the saturated fats in dairy that may help nullify their effects on our health.
The good news…
Vitamin and mineral content remains high no matter the fat percentage
If you prefer lower-fat milk, know that skim and low-fat milk have just as much protein, calcium, potassium, and phosphorous as whole milk. In fact, skim milk has slightly more of all these nutrients compared to whole milk.
You will still absorb those fat-soluble vitamins even with fat-free milk
Fat-soluble vitamins include vitamins A, D, E, and K.
Previous research and theory indicated that these fat-soluble vitamins may be best absorbed when taken WITH a meal containing fat.
However, your body isn't going to absorb these nutrients immediately after a meal. Nope. Instead, your food is going to sit in your stomach for a while churning away, then it's going to sit in your intestines for up to 48 hours. You have plenty of time to eat other fat-containing meals to provide the fats needed to help these vitamins be absorbed.
In fact, a new study showed that you can take a fat-soluble vitamin supplement on an empty stomach and then eat a fat-containing meal 12 hours later and STILL absorb those nutrients!
Does dairy help with weight loss?
A meta-analysis of dairy and weight loss studies showed that when someone is in a calorie deficit (trying to lose weight) and they eat a higher dairy diet (2-3 servings of dairy daily), they lose more body fat while losing less muscle mass when compared to people trying to lose weight with a lower dairy intake.
But here's the clincher:
When people included resistance training while on a calorie restriction, consuming dairy didn't make a difference in their fat loss or muscle mass maintenance.
So if you're going to lose weight and not do resistance training, you may want to have 2 to 3 servings of dairy per day as part of your diet. But if you're lifting some weights, no need to add dairy.
Does cow's milk help with exercise performance?
Unfortunately, studies do not agree on this topic.
Studies have been done on resistance exercise and endurance, and while some show improved recovery and performance, others do not. So at this point, we can't make a definitive statement on its benefits.
However, dairy does contain protein and carbohydrates, so if used correctly, you may find it beneficial as a recovery drink.
More studies are needed!
What about Raw milk?
Raw milk is milk that has not been pasteurized. Pasteurization is when milk is heated to a temperature that kills harmful bacteria and parasites.
Remember, milk comes from a live animal and there are many ways for it to become contaminated.
One of the most dangerous things you can do in your diet is to drink raw milk. Raw milk can carry E. coli, Listeria, Salmonella, Brucella, Campylobacter, and Cryptosporidium. It can even put you at risk of developing Guillain-Barre Syndrome.
Raw milk does NOT have more benefits. You're getting the same nutrients from pasteurized milk as from raw.
Please. Just get pasteurized milk.
Bottom line
Overall, current research indicates that a couple of servings of dairy daily may be a perfectly fine addition to your diet.
And you no longer have to worry about fat percentage! (in most cases)
The only drawback is your weight. If you add a bunch of high-fat dairy to your diet (which is also relatively high-calorie), be sure to take something else out of your diet to help balance your caloric intake.
Sources
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Stonehouse W, Wycherley T, Luscombe-Marsh N, Taylor P, Brinkworth G, Riley M. Dairy Intake Enhances Body Weight and Composition Changes during Energy Restriction in 18-50-Year-Old Adults-A Meta-Analysis of Randomized Controlled Trials. Nutrients. 2016;8(7):394. Published 2016 Jul 1. doi:10.3390/nu8070394
Alcantara, J. M. A., Sanchez-Delgado, G., Martinez-Tellez, B., Labayen, I., & Ruiz, J. R. (2019). Impact of cow’s milk intake on exercise performance and recovery of muscle function: a systematic review. Journal of the International Society of Sports Nutrition, 16(1). https://doi.org/10.1186/s12970-019-0288-5
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