When people decide to improve their gut health, the first instinct is almost always to start cutting things out. Research actually points the other way, what you add matters as much as, often more than, what you take away, which makes this a far easier project to start than most people assume.
Adding before removing tends to work better on every front. A varied, fiber-rich diet naturally creates conditions where beneficial bacteria thrive and crowd out the ones causing trouble, so before cutting anything, think about what could be added instead, a daily fermented food, one more vegetable at dinner, a tablespoon of seeds in morning oats, a tin of beans at lunch. Adding is psychologically easier than restricting, fits social eating far better, and has strong research behind it.
Aiming for 30 different plant foods a week is a good target here. One large study found that people eating 30 or more different plant foods a week had significantly more varied gut bacteria than those eating fewer than 10, and every distinct vegetable, fruit, bean, grain, nut, seed, herb, and spice counts separately. Once you start actually counting, 30 comes faster than most people expect.
Making fermented food a daily habit is genuinely worth it. A 2021 clinical trial found that a diet high in fermented food increased gut bacteria variety and lowered inflammation markers more than a high-fiber diet alone over 17 weeks, and combining the two worked even better.
One distinction worth holding onto: ultra-processed foods specifically disrupt your gut through additives that damage the protective mucus lining, but not all processed food falls into that category. Tinned beans, frozen vegetables, canned fish, plain yogurt, and whole grain bread are all perfectly fine for your gut.
Count your plant food variety across seven days, every distinct plant food you eat. Most people land somewhere between 8 and 15. Then find the single easiest addition, a new vegetable each shopping trip, fresh herbs on dishes you already cook, a different grain than usual, seeds on breakfast, and add a fermented food daily alongside it. Add first, don't cut anything yet. After four weeks of consistent additions, that's the point to look at which ultra-processed foods still earn a place in your diet.
This content is for educational purposes only and is not a substitute for professional medical advice.