Can milk make you fat? You can overdo it, for sure. Don’t expect to be able to drink a gallon of milk every day without gaining some extra fat. But if you’re only drinking a few servings a day, milk will help you avoid getting fat.
Why do we gain fat?
The process of storing fat means you’re eating more energy than you’re burning off. (One of the best ways to prevent fat gain is exercising, check out our free bodyweight workout here.)
So, let’s say, you’re at energy balance (calorie maintenance), which means you’re not gaining any weight.
Then you begin adding in a glass of milk with each meal. You’d now be consuming more energy than normal, and you’d expect your body to store those extra calories as fat.
But instead, we find something unusual happening.
Milk is designed to get you more muscular, strong and healthy—not overly fat
If you think about the goal for human breastmilk to a baby or cow’s milk for a calf, the goal isn’t to get them bigger by getting them fatter. The goal is to give them everything they need to become bigger through growth while keeping them healthy.
Building bigger muscles, building stronger bones to support those muscles, having good nutritional value to stay healthy during the process, etc.
And that’s what we find the research showing.
In 2012, researchers reviewed 14 studies and found that dairy, like milk, won’t cause people’s weight to change. If someone wants to get lighter or heavier, they’d need to get into a calorie deficit or surplus intentionally.
But what researchers found was that while those drinking milk didn’t have the number on the weight scale change much, having dairy changed their body composition.
Those drinking milk got *less fat* and built more lean mass.
The average person lost 0.72 kg (1.5 lb) of fat and gained 0.58 kg (1.3 lb) of lean mass. They also lost 2cm on their waist circumference because they burnt off some fat.
So while they didn’t lose a lot of weight, they became more muscular and leaner, with a flatter stomach.
And in 2019, researchers studied over 12,000 people, and they found that drinking as little as one serving of milk made your body build more lean mass. Not only that, but you’d get a better ratio of subcutaneous to visceral fat. That means you’d not only be stronger, but you’d get more “good” fat and less of the bad kind around your organs.
Why does milk build muscle and help to keep people lean?
There are a few ways milk does this:
- Milk has high levels of protein per serving. One glass of milk is nearly 9 grams of protein. Protein helps to build muscle and is very difficult for our body chemically convert it into energy or fat—so excess protein often gets burnt off as body heat.
- Milk is the top scoring protein in terms of quality. Milk also contains whey and casein—two of the top muscle-building supplements for building muscle. Milk is the top quality protein, meaning it’s the easiest protein to digest to build muscle, and it contains all the essential amino acids our body’s need.
- Milk contains fat-burning compounds in the fat. Inside the fat of the milk, there are around 400 different fatty acids. One of these is fatty acids is called CLA—conjugated linoleic acid. CLA is a compound that helps to fight off cancer, diabetes, obesity, and fatty plaques from forming in the arteries (heart disease). It helps to prevent too much fat gain and helps to burn fat. (paper)
- Milk contains dietary cholesterol and saturated fats that will help your body to build lean mass. These compounds, consumed in a moderate amount, will help your body work properly. (study, study)
- Milk is incredibly satisfying, so it can make overeating with other foods less likely. When milk makes you full and satisfied, you’re less likely to go hunting through the cupboards for more food. Part of this is because milk is so high in protein, which can reduce cravings. But researchers think there may be something unique about the structure of milk protein that makes it especially satisfying.
Should you drink skim milk to reduce calories?
I suspected that drinking skim milk would help people stay lean because it contains less calories, and you’d get a higher protein ratio overall. For one cup, skim milk has around 70 calories less than whole milk.
However, the research proved the opposite was true (again.)
- In this review on high-fat dairy, researchers found that having full-fat dairy was associated with a lower risk of becoming obese.
- In this study, people who ate butter and cream, and drank whole-fat milk, had less of a belly.
- In this study of close to 20,000 women over nine years, the women who consistently had whole fat milk and cheese had an inverted relationship with weight gain. Meaning that the women having whole fat milk and cheese didn’t get fatter over the nine years. But those who had no milk or they had the low-fat milk didn’t get those same benefits.
- In these two studies (study, study), having full-fat milk was associated with having a lower risk of metabolic syndrome.
- In this 2016 study, those who had dairy fat had less risk of getting diabetes.
What’s going on here?
Perhaps there is a reason for those 400 fatty acids to be there in the milk? When we play with the milk, and we remove all the fats as we do with skim milk, we’re affecting the way the milk works.
Overall, drinking whole-fat milk will not only help to maintain a healthy body weight, but it should also make you stronger at the same time. Not to mention, you’d get dozens of other health benefits. (See all the health benefits in our super-guide on milk.)
Organic milk could help even more with staying lean
Organic milk is when cows are raised on the pasture a certain amount of time of the year (among some other things.) The USDA requires the cows to eat from pasture a minimum of 120 days.
In this study, researchers found:
“The output of vitamins in milk was within farm positively correlated to supply of vitamins from roughage.”
That means, to put the vitamins and fatty acids in her milk, the cow needs to be eating properly.
In a 1999 study, researchers studied cows fed a variety of diets like the differences when cows ate corn silage, alfalfa hay, and going out to pasture.
Researchers found that the cows that ate 100% of their diet from the pasture had 500% higher levels of CLA compared to eating a conventional diet. That was 22mg of CLA per gram of milk compared to just 3.9mg per gram of milk.
Earlier we mentioned how CLA not only helps to prevent fat gain and tells our body to burn fat, but that it can protect us from cancer, diabetes, obesity, and fatty plaques from forming in the arteries causing heart disease.
And in this study, it found that organic milk had 62% more omega-3s than conventional milk.
Organic milk isn’t 100% grass-fed, but it’s a start. If you have access to (and can afford) grass-fed or organic milk, you may want to give it a try for maximizing the benefits milk can provide.
- A review of 14 studies found that milk doesn’t make people’s weight change, but it does help body composition. Most people gained a bit of lean mass and burnt a bit of fat.
- One study found that milk helped to build muscle mass, and fix the ratio of subcutaneous fat (good fat) to visceral fat (bad fat.)
- Has high levels of protein per serving
- Is the top-scoring protein in terms of quality
- Contains fat-burning compounds like CLA in the fat.
- Contains dietary cholesterol and saturated fat for optimal hormone production
- Is very satisfying and could reduce overeating
- Whole fat milk, paradoxically, is better than skim milk
- Whole milk is associated with a lower chance of becoming obese or getting diabetes
- People who ate butter, cream, and full-fat dairy had less of a belly
- Whole fat milk was inversely correlated with weight gain for women over 9 years
- Whole fat also helps to build more muscle than skim milk
- Organic and pasture-raised cows have more of the top compounds in the fat of their milk, like CLA and omega-3s.
- 100% pasture-raised cows had 500% higher levels of CLA compared to their normal diets.
If you want to learn more about how milk:
- Affects your health like cardiovascular disease and cancer
- Helps you to build muscle and burn fat
- The differences between organic and conventional milk
- What the story is between A1 and A2 milk
- How homogenization and filtering affects milk