Most of us were brought up to believe that dairy is a key part of a healthy diet: It was touted as an essential source of calcium, protein, and vitamin D, and a staple of the food pyramid. We learned the importance of dairy in magazine ads, billboards, and TV commercials that showed milk-mustachioed celebrities asking: "Got milk?" Dairy is accessible, cheap and for decades has been an integral part of kids' breakfast routine. But now research tells us that there are health reasons to avoid dairy and that it isn't as beneficial as we were raised to believe. Athletes, especially are staying away from dairy because of what they report as performance-related issues.

The Truth of Dairy and Your Health. First, What's In the Milk Now Isn't Pretty

Dairy today is not your grandmother's milk. The process of farming has vastly changed in the past two generations, and in an attempt to increase milk production and cut costs, in the early 1990s, cows were put on diets of soy, grain, and corn. While their stomachs were designed to digest grass, which is naturally high in Omega-3, the cheaper diet changed the makeup of their milk, increasing the Omega-6 content of the milk, which is less healthy to consumers. The cycle continues, as cows are over-fed antibiotics to keep the disease-free, but these drugs then enter the milk humans drink.

Not only does the excess of antibiotics make us antibiotic-resistant and more vulnerable to infection, but it damages the internal flora of our gut health, making it yet harder to digest dairy.

An estimated 65 percent are now lactose intolerant, and many more get aggravated by drinking dairy, since the enzyme needed to absorb lactose, called lactase, is only present in the human body in our infancy.

"A deficiency of lactase can cause what is known as "lactose malabsorption," where undigested lactose passes into the colon, where it is broken down by bacteria, creating fluid and gas. This leads to the symptoms commonly associated with lactose intolerance: abdominal bloating, diarrhea, gas, and nausea. The amount of lactose someone with lactose intolerance can tolerate before experiencing symptoms varies greatly, depending on the individual and the type of dairy product they're consuming," according to Stacked, about why athletes from Novak Djokovic to Tom Brady, have given up dairy.

Athletes Who Have Asthma or Thick Mucus Should Avoid Dairy, Meat and Eggs

Many people report that dairy increases the amount of mucus or phlegm when they exercise, and studies do connect milk and dairy to the thickness or production of these annoying byproducts when your body reacts to triggers in your diet.

While a diet rich in fiber reduces inflammation and lowers risk of asthma, a diet of cheese and dairy appears to increase the risk of asthma, according to a study published this past spring.


The Lung Institute, which researches lung health, has identified a list of foods to avoid if you have trouble breathing, either because of chronic ailments such as COPD or exercise-induced asthma. Even adding just one serving a day of fruits and vegetables was enough to lower asthma symptoms, while adding ricotta cheese appears to make symptoms worse.

These 21 foods have been identified as increasing mucus or thickening it, creating trouble for anyone who is out for a run or is sensitive to pollutants in the air or food. The list of foods to avoid are below. Notice that five of the top ones are dairy:

The 21 foods to remove from your diet:

  1. Red meat
  2. Milk
  3. Cheese
  4. Yogurt
  5. Ice Cream
  6. Butter
  7. Eggs
  8. Bread
  9. Pasta
  10. Cereal
  11. Bananas
  12. Cabbage
  13. Potatoes
  14. Corn and corn products
  15. Soy products
  16. Sweet desserts
  17. Candy
  18. Coffee
  19. Tea
  20. Soda
  21. Alcoholic beverages

Dairy is High In Saturated Fat, Which Causes Heart Disease

Even if you are not sensitive to the lactose in milk, and can digest it without side effects, there are other serious issues with dairy products. When trying to be heart-healthy, research supports avoiding saturated fat found in whole milk, butter, and most cheeses. Studies show that saturated fat can lead to an increased risk of heart disease by promoting high cholesterol, calcium deposits, and eventually plaque that cause hardening of the arteries, not such an athletic sounding outcome. Despite years of debate, recent studies show that a diet high in saturated fat increases the lifetime risk of cardiovascular disease.

Additionally, cheese has been shown to be addictive, as casein, the protein in dairy, causes our brains to light up as they do when we eat chocolate or other sweets. Casein is literally the stuff wood glue is made of, and it's basically the same thing in our arteries, yet the dairy industry continues to tout the benefits o dairy as a post-workout protein source. Dr. Neal Barnard, M.D., F.A.C.C , writes in his book, The Cheese Trap: “Sky-high levels of cholesterol and saturated fat in dairy products, have been proven to increase all cardiovascular problems, yet tens of millions of government dollars are spent each year subsidizing marketing and promotion of the cheesiest meals at fast-food restaurants.”

Health Effects Caused by Dairy Include an Increased Risk of Cancer

Even milk that claims to have "no added hormones" is essentially false advertising, as the natural estrogens that are occurring in the cow get passed to the milk. These are the same hormones that enabled the cow to produce the milk in the first place. But in humans, they take on a more sinister role of promoting estrogen growth of potential hormonal cancers, such as breast and more. No runner needs any extra estrogen to perform better. A 2020 study found that drinking just one cup of cow's milk a day can increase a woman’s relative risk of breast cancer by 50%, and in men, these hormones can lead to prostate cancer.

The Best Source of Calcium is Not Milk, It's Vegetables and Dark Leafy Greens

Another one of the most common health claims is that milk is the best source of calcium, which is beneficial for muscle contraction, nerve conduction, and contributes to bone health. Surprisingly, it's not the cows that make the calcium, but the plants and grass they eat that provide these nutrients. The same calcium can be found in a cleaner, less fat-laden source: The dark leafy greens and vegetables you find at the farm stand, are more reliable sources. Consider that only 30% of the calcium in milk is absorbed by the body, while 50% or more of the calcium in leafy greens are. So sipping that green smoothie right before your run is even more valuable that any glass you might drink.

Drinking milk has not been shown to be protective against osteoporosis, or eventual hip fractures, but the opposite is actually true: A diet high in dairy as a teenager had no effect on the number of bone fractures in women and led to 9 percent higher incidents of hip fractures in men later in life. Additionally, vitamin D has been that was added to milk to make it easier to promote as a healthy source of the necessary vitamin, but athletes can get their daily dose by running outside, n the sunlight, or taking a D supplement. The amount of vitamin D to take to increase immunity depends on the individual.

Does Milk Really Lead to Strong Bones? It May Lead to More Hip Fractures

Other key problems that can be caused by consuming dairy are bloating, inflammation and digestive issues. The sugars found in lactose causes blood sugar spikes, results in inflammation, not only affecting athletic performance but also the immune system. In a study done by a leading gastrointestinal specialist, Mervyn Danilewitz M.D. states that the number one cause of stomach pains amongst runners is dairy products such as milk and cheese, and advises athletes not to eat dairy 24 hours before running. The main culprit is the lactose that 65 percent of us can’t digest, which can lead to stomach pain, gas and diarrhea. Intolerances like this might not become apparent until you start running, as the added strain on your body means digestion suffers, and as any runner knows, that is a situation no runner wants to be in.

If you usually go for a quick coffee before your run, maybe add in a splash of oat or almond creamer and give yourself enough time to make sure your stomach is clear. If your go-to breakfast is a quick fruit and yogurt or cottage cheese, choose ones that are nut-based, that are super creamy and full of heart-healthy ingredients, with none of the sodium that is present in the dairy versions. Or if you’re carbo-loading the night before, make sure you don’t eat anything that would hinder your performance, and use plant-based cheese in your Alfredo sauce.

Seeking out dairy-free alternatives has never been easier, and each day there seems to be another product hitting the shelves, whether its plant-based milks, creamers, cheeses or ice creams. It’s all about trying out what’s right for you and how you feel on your workouts. Skip the dairy and see if you feel better, breathe more easily and recover faster. The Game Changers documentary shows athletes at the top of their sport enjoying more endurance and quicker recovery times on a plant-based diet. After all, when you’re putting in all the stretching, hard work and recovery, learning more about what we’re led to believe and making a little change to your diet is nothing compared to all the benefits.

Athletes that leave the Dairy Behind Tell Their Fans to Do So As Well

Rich Roll, author, blogger, ironman triathlete, and ultra-distance athlete had a health scare at 39–he had chest pains and thought he was having a heart attack. Back then, as an over-worked, over-stressed corporate attorney, living a sedentary life and about 50 pounds overweight, he realized he needed to change things up.

Roll explains that he was feeling "unenthusiastic" about his life and having "a spiritual crisis" at the same time that his health was beginning to falter. When he felt tightness in his chest heading upstairs to his bedroom, he recalls it was a moment where" everything crystalized" and he realized he could not keep living this way. Roll explains in an interview that he had a sense of urgency and the willingness to do something about it.

So that moment caused him to change his diet and lose 50 pounds, setting him on a road to athletic glory as an endurance competitor, author and vegan influencer. That was the beginning of his journey: He started by doing a juice cleanse and then eventually he went vegan, got off the junk food, and became a poster-athlete for the benefits of a plant-based diet and now he tells fans and readers that this diet change not only sent him down a new path but helped him in every way.

"What you put into your body really does impact how you look and feel," he found. He got rid of the animal products and processed junk and within seven to 10 days of making the switch he felt like a completely different person. He would ask: what are you waiting for? A heart episode? A crappy workout? If you want to make the switch, do it today.

Staying away from dairy boosts heart health and recovery time, lowers inflammation, helps improve arterial flexibility, and helps digestion, a key factor in maintaining endurance, strength and speed. So if you’re a runner or athlete or anyone who cares about how to fuel your active body, make the switch to dairy-free milk and cheese, and let us know how it's going.

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