Dr. William Li spoke with us on what he eats every day to not only stay healthy but fight off chronic diseases like cancer and diabetes.  
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Dr. William Li is a Harvard-educated doctor of internal medicine who has dedicated himself to bridging the gaps between medical treatment and nutrition for 20 years. More than two decades of research and experimentation have helped him identify more than 200 foods that actually work with our body’s five defense systems to fight off diseases like cancer, diabetes, and dementia. 

From strengthening our microbiomes to helping our body regenerate healthy cells, these foods are seriously powerful and worth adding to our diets. Check out his five favorites, here

So, what are these special foods a Harvard cancer researcher eats every day, you ask? Luckily, Dr. Li shared his daily diet with us, and spoiler alert: it actually sounds like a delicious way of living! And you don’t have to buy any weird or expensive products to do it. 


Credit: Photo: Jamie Vespa

Dr. Li kicks off each morning with a cup of coffee or green tea (Harvard docs, they’re just like us!) Li calls coffee and green tea “grand-slammer foods,” because they activate all five defense systems in the body for optimal health. He loves matcha green tea in particular for its extra-concentrated antioxidant power. 

Li also loves starting his day off with some other “grand-slammer foods” like mango and fresh berries, which he serves alongside a bowl of hearty, high-fiber oatmeal. We think Dr. Li would love our power-packed Berry-Banana Overnight Oats or our omega-3-rich Orange-Mango Gritty With Turmeric and Walnuts for a serious anti-inflammatory boost. 


Credit: Photo: Jennifer Causey

Dr. Li likes to keep it simple for lunch, often opting for a big leafy green salad, full of nutrient-dense kale, spinach, arugula, or radicchio. He likes to eat something green every day, and yes, avocado counts!

Lunch is also a great time for a midday pick-me-up, and Li likes to serve up some legumes for a boost of plant power. Legumes like lentils, chickpeas, and black beans are loaded with protein, fiber, iron, and a host of other vitamins and minerals. Li regularly eats lentils with balsamic vinegar, extra virgin olive oil, and a squeeze of fresh lemon juice. Yum! 

Try our Lemony White Bean-and-Arugula Salad for a nutritious lunch in less than 10 minutes, or our Summery Lentil Soup (which is perfect for those who prefer to meal prep their lunches for the week). 


Credit: Jennifer Causey

Dr. Li is sure to eat a handful of tree nuts almost every day, and his personal favorite is walnuts. Walnuts are full of omega-3 fats, which boost your brain and immune system, and they also are a great source of B vitamins and magnesium. 

Dark chocolate also makes its way into the mix when Li needs something sweet in his life. Dark chocolate is another one of his “grand-slammer” foods, and he prefers varieties made with 70 percent or more cacao. We think our Spicy Dark Chocolate Tahini Bark would be just what the doctor ordered when craving sweets (pun intended). 


Interested in learning more about the world’s healthiest foods?


Credit: Photo: Caitlin Bensel

Fish is one of Li’s favorite foods for fighting off disease, and what better way to serve it than with pasta? Li enjoys a small serving of yellowtail with whole-wheat pasta, antioxidant-rich tomato sauce, and garlic scapes with capers and lemon. 

Li believes carbohydrates are an important part of fighting off disease—you just have to go for the right ones! Opting for whole grains, fruit, beans, and gut-friendly sourdough bread over refined or processed carbs is key to reaping the disease-fighting benefits.

Try mixing up your fish intake with some halibut or sea bass in our Caribbean-Spiced Fish Wrapped in Banana Leaves and definitely add our One-Pot Pasta With Spinach and Tomatoes to your next weekly meal plan. 

Dr. Li’s diet makes us feel like we can actually eat to fight off disease and enjoy it too! Check out his book, Eat to Beat Disease: The New Science of How Your Body Can Heal Itself and his shopping guide of 200 disease-fighting foods on his website at Dr.WilliamLi.com.