Dr. Ezekiel Emanuel spends his days thinking about cancer risk and health policy. He also, apparently, spends some of them eating ice cream. Over a bowl of pen-and-paper-flavored ice cream in London this June, the 68-year-old oncologist, public health professor, and former Obamacare advisor laid out the diet advice he actually gives people — stripped of wellness-industry noise, and built around four changes he says give you the most benefit for the least effort.
“I’m anti the wellness industrial complex,” Emanuel said. He’s “vehemently” against tracking, obsessing over, and optimizing every input of your health, and argues wellness should fit around your life, not the other way around. His approach, laid out in his new book, comes down to four starting moves.
Key Takeaways
- Dr. Ezekiel Emanuel, an oncologist and public health professor, recommends four starting changes: eat fermented foods, cut back on soda, reduce ultra-processed snacks, and get more fiber.
- He calls fermented foods “the easiest small change with big benefits” for gut health.
- Drinking 1-2 sugary sodas a day is linked to a roughly 26% higher risk of type 2 diabetes, a figure that matches a well-established medical research meta-analysis.
- Most Americans already get enough protein but fall well short on fiber, getting roughly half the recommended amount.
1. Add Fermented Foods
Emanuel’s first recommendation is also, in his view, the easiest: foods like sauerkraut, miso, kimchi, and kefir. Fermented foods contain both prebiotics (plant fibers your body can’t fully digest) and probiotics (live bacteria), which together feed beneficial gut microbes. Research has linked regularly eating fermented foods to a more diverse gut microbiome — generally considered a marker of good health — along with a lower risk of obesity and a stronger immune system. “Pick whichever ones you like,” Emanuel said. “They’re really, really good for you.”
2. Cut Back on Soda
Emanuel’s second recommendation is to stop drinking sugary soda, or at minimum cut down to one or two glasses a week. He cited a roughly 26% higher risk of developing type 2 diabetes among people drinking 1-2 sodas a day — a figure that lines up closely with a well-known meta-analysis published in Diabetes Care, which found that people in the highest category of sugar-sweetened beverage intake had about a 26% greater risk of type 2 diabetes than those drinking less than one serving a month. He also linked regular soda consumption to heart disease and fatty liver disease. A 12-ounce can, he noted, contains about 140 calories and roughly 10 teaspoons of sugar, with no nutritional value in exchange. It’s worth noting that diet soda isn’t automatically a clean swap either — other reporting on nutrition research has found that while it can be a helpful bridge away from sugary drinks, diet soda may still affect gut health in its own way.
3. Cut Back on Ultra-Processed Snacks
“We all have to cut back on the packaged snacks,” Emanuel said. The average American gets around 60% of daily calories from ultra-processed or “junk” foods — packaged muffins, cookies, chips — which tend to be high in salt, sugar, fat, and additives while offering little nutritional value. Regularly eating these foods has been linked to a higher risk of diabetes, cardiovascular disease, cancer, and depression, and some research suggests certain common additives may disrupt the gut microbiome. Emanuel prefers the plainer term “junk food” over “ultra-processed,” since the more technical term has become a contested one in nutrition science — it can lump genuinely healthy staples, like packaged whole-wheat bread, in with items like doughnuts and hot dogs that share little in common nutritionally.
4. Get More Fiber
Despite the cultural fixation on protein, Emanuel says most people already get enough of it. What’s actually missing from most American diets is fiber. Adults need roughly 30-35 grams a day, he said, but the average American gets about half that. Fiber slows how quickly glucose enters the bloodstream, helping avoid sugar spikes and crashes, and feeds beneficial gut bacteria. Good sources include berries, pears, apples, kiwis, broccoli, sweet potatoes, beans, nuts, and whole grains. His practical starting point: fruit throughout the day, and a salad with dinner.
The Bigger Picture
Emanuel is careful to frame all of this as a floor, not a rigid rulebook. “Getting on the right diet is relatively simple,” he said. “There are four things you should do to start, and then there are things you can add.” And treats still have a place: as he put it in his book, “the occasional treat will not shave any minutes off your life, especially if you enjoy it with someone you love.”
Source: Schewitz, K. (2026). “A top cancer doctor shares 4 bare minimum food rules to lower your chronic disease risk.” Business Insider, Aug. 15, 2026; Malik, V.S., et al. (2010). Sugar-Sweetened Beverages and Risk of Metabolic Syndrome and Type 2 Diabetes. Diabetes Care, 33(11), 2477-2483.