The Science Behind a Plant-Based Diet

When you learn that Chris Hemsworth went on a plant-based diet while filming “Thor” and “Avengers,” it’s not only surprising but also gets you thinking! You might find it to be a risky diet for someone who needs to maintain his superhero shape.

When you read that Lewis Hamilton, a five-time Formula 1 Champion, eats a strict plant-based diet, it hints that there must be a good reason behind it!

And the list extends to tennis star Serena Williams, mixed-martial-arts fighter Mac Danzig, football player Tom Brady, and more. All of these celebrities have intense workout regimens and career demands, so why did they choose to go plant-based?

Before getting to that, here is a quick intro to plant-based nutrition for those who are not so familiar.

What is a plant-based diet?

This type of diet calls for foods primarily from plants, including nuts, seeds, whole grains, legumes, and beans. A plant-based diet minimizes processed foods, dairy, meat, and animal products. It encourages fresh, whole foods, as opposed to packaged and refined foods.

Plant-based diets can vary depending on the approach. Check out these prominent types:

Whole-food plant-based (WFPB) diet

The focus here is on eating plant-derived whole foods that are minimally processed and unrefined. The idea is to eat plant-based foods in forms as close to their natural state as possible. No added salt, sugar, or oil.

Strict plant-based diet or vegan diet

In this diet, foods can only be from plant-based sources. This diet excludes meat, seafood, dairy, and all animal products, including honey. It may include added fats, refined carbs, salt, and processed foods.

Vegetarian diet

This diet is predominantly plant-based but includes animal products like dairy and eggs. It excludes meat, poultry, and seafood. It allows added fats, refined carbs, salt, and processed foods.

Going predominantly plant-based has many health benefits for your body. It lowers the risk of many degenerative diseases such as heart disease, diabetes, high blood pressure, and stroke. Besides, here are the top science-based reasons why plant-based is the most suitable diet for many people!


The science behind plant-based meals

#1 Physiological evidence 

Our digestive system is a clear affirmation that we are herbivores!

Mouth: Our mouth is the starting point for digesting food. It is the first evidence that we are not equipped to eat meat. Human teeth are for biting, grinding, and chewing the plant matter. The saliva of all herbivores contains alpha-amylase, the enzyme that helps to break down starch. It is the first digestive enzyme that comes into contact with food. On the other hand, a carnivore’s mouth is meant for cutting and tearing, and it is devoid of saliva. All carnivores have sharp, blade-like teeth for slicing meat, and humans lack this type of teeth.

Digestive tract: The human stomach is smaller and moderately acidic when compared to carnivores. Our intestines are long, which facilitates a slower digestion process so we can absorb more nutrients from the food. A carnivore’s digestive tract has a large stomach with highly concentrated acidic juice to kill bacteria in the raw flesh of its prey. The intestines are short and are equipped to move the meat out of the digestive tract, so it does not begin to rot.

#2 Plants are gut-friendly.

The human gut is a host for thousands of different types of bacteria, collectively called the gut microbiome. Your gut bacteria are crucial for improving digestion, nutrient absorption, making vitamins, blocking pathogens, and boosting the immune system. Your health is mainly dependent on the gut microbiome. The more diverse the gut bacteria, the higher the health benefits. Studies show that gut bacteria thrive on undigested plant material called dietary fiber. Dietary fiber from nuts, seeds, grains, and leafy greens contain carbon that helps the beneficial bacteria to grow. Meat and other animal foods cannot provide dietary fiber.

#3 You need antioxidants, and plants provide plenty of them.

Normal metabolic processes, such as breathing, digestion, walking, etc., can lead to byproducts called free radicals. These are unstable molecules that can damage your DNA (genetic material) and lead to a plethora of degenerative conditions. Antioxidants help mitigate this effect by stabilizing free radicals. Your body makes its antioxidants and also relies on food sources for antioxidants to keep up with the free radical production. Luckily, plant foods such as berries and dark chocolates are super rich in antioxidants and protect you from free-radical damage. The number of antioxidants in animal products is small when compared to plants. Another advantage is that plants provide a diverse source of antioxidants and offer many health benefits.

 #4 Promotes longevity 

Plant-based foods are low in the amino acid methionine, which can damage genetic material (DNA) and cells. Research reveals that less methionine from foods indicates a longer life span [8]. Animal foods like meat and poultry are rich in methionine, which is the root cause of health issues like Alzheimer’s and other neurologic disorders. According to a meta-analysis of studies, replacing red meat with plant proteins such as lentils and beans lowers the risk of heart disease. Researchers found improvement in blood lipid levels and noted that a boost in fiber and antioxidant intake, alongside decreased saturated fat and cholesterol consumption, might be the reason for the lowered risk.

Choosing a Plant-Based Lifestyle

There are a host of other benefits when you choose a plant-based lifestyle, such as healthy body weight, improved mood, stronger bones, and better focus. Beware, not all plant-based foods are necessarily beneficial to you. French fries are technically vegan, but they are not exactly health-promoting. For this reason, it is best to go with the whole-food plant-based diet since it focuses on wholesome and unprocessed foods.

If you cannot follow 100% plant-based eating, it is best to aim to eat mostly plants 80% of the time. Any eating plan that encourages more plants and very few animal products can improve your health. There are a host of nutrients that should be monitored when choosing a plant-based lifestyle. Two common nutrients to monitor are vitamin B12 and iron. Be sure to consult with a registered dietitian for further questions. 

It can be overwhelming in the beginning to limit or quit meat and begin eating predominantly plant-based. But with well-planned meals and a handy shopping list, the transition can be smoother. Fortunately, there are many resources online and at your library, and they can be great places to start.

The Juice Bar has delicious plant-based options that will make for a tasty transition. Choose a plant-based protein in your smoothies and swap out meats for beans and tofu on your favorite items.

Going plant-based is not only a tremendous benefit for your health, but it is also good for the planet. By all means, go for it!


Milton K.  Hunter-gatherer diets-a different perspective.  Am J Clin Nutr. 2000 Mar;71(3):665-7.
Cavuoto P, Fenech MF. A review of methionine dependency and the role of methionine restriction in cancer growth control and   life-span extension. Cancer Treat Rev. 2012 Oct;38(6):726-36.
Ferré MG, Satija A, Blondin SA, et al. Meta-analysis of randomized controlled trials of red meat consumption in comparison with various comparison diets on cardiovascular risk factors. Circulation. Published online April 8, 2019.

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