If you’re like me, you’d be surprised that eating plants is a contested topic in the wellness space. I grew up in an “eat your vegetables” house where there was no doubt that eating a variety of plants was the pinnacle of health. Of course, this is largely true. Plants contain micronutrients and feed our microbiome with fiber so that it creates byproducts, like serotonin, that we use. They also contain polyphenols, like resveratrol, that send epigenetic signals that improve our health by, for example, reducing inflammation or producing antioxidants. However, plants also can trigger sensitivities that cause more harm than good.

Unlike animals that evolved to fight or run to avoid becoming dinner, plants can protect themselves only with chemicals. While some parts of plants, like fruits, are intended to be eaten to spread seeds, other parts of plants, like seeds, need to avoid being eaten. As a result, they evolved chemical defenses that harm animals that try to eat them, called lectins. Anything intended to help a plant grow – such as seeds, nuts, and beans – contains lectins.

While humans are too big to be seriously harmed by lectins, they can still cause significant distress in our gut. Because half of our immune system surrounds the gut (aka where foreign objects are processed and passed into our bodies), gut distress and improper processing can lead to significant inflammation in the body. For the same reason, people have varying tolerance to gluten. Gluten contains a protein that causes some leaky gut, allowing material from the gut to escape and causing the immune system to deal with it. How sensitive people are to lectins or gluten depends on the composition of their gut microbiome.

The composition of your gut microbiome can also make you sensitive to other kinds of plants. For example, I feel bad when I eat spinach because my microbiome doesn’t include the bacteria that break down oxalates. In addition, I avoid raw tomatoes because my microbiome includes the tomato mosaic virus. Cutting these out of my diet was no problem because they make me feel crummy, and I’ve developed a taste aversion for them. Other common sensitivities include FODMAP foods, such as onions and garlic, and nightshades, such as eggplants and peppers. If you find that some vegetables make you feel bloated and fatigued, you might look these categories up and cut out these foods to see if it helps.

Rule 1: I eat at least one serving of leafy greens, cruciferous vegetables, colorful fruits or vegetables, seeds/nuts/beans, and fermented food per day.

Each category provides a healthy dose of polyphenols, micronutrients, and pre- or probiotics. The categories come from the book Younger You by an author who studies epigenetics and nutrition. More servings would be better, but getting some of each category daily provides most of the benefit. If I had to pick just one of these to prioritize, it would be cruciferous vegetables. If you keep sauerkraut or kimchi (fermented cabbage) on hand, you can knock out leafy green, cruciferous, and fermented all at once. In addition to the daily categories, I have blueberries and beets three times a week (which count as colorful fruits or vegetables).

Rule 2: I prioritize whole plants, including raw fruits and cooked vegetables.

Some people avoid fruit because it contains a lot of sugar, but I don’t worry about it as long as I’m eating raw fruit and it fits within my carbohydrate intake. I avoid grapes and bananas, though, because they are very high in sugar, even raw. Raw fruit includes enough water and fiber so that it fills you up and doesn’t digest too quickly. Be careful with other forms of fruit because juiced fruits (or even high sugar vegetables) remove the fiber, and cooked or dried fruits remove the water. Cooked and dried fruits are often also sweetened.

Vegetables, in contrast, I rarely eat raw because they don’t digest easily enough. I roast my vegetables or saute them in a skillet as part of dinner, leaving them cooked yet crisp. For seeds and nuts, I make sure that they are roasted. For beans (cooked from dried), I soak them overnight so that they start to sprout and then thoroughly cook them. Once beans or grains have sprouted, they’re generally much easier to digest.

For more information about how plants are good for you, check out this interview with Dr. Will Bulsiewicz, who studies the microbiome and discusses the potential long-term effects of paleo, keto, and carnivore diets. His bias, and the interviewer’s, is toward plant-based diets. To balance that perspective, check out this interview with Dr. Steven Gundry. He wrote The Plant Paradox and spends most of his time treating people with chronic diseases caused by plant sensitivities, like autoimmune disorders. Both talk about the importance of eating plants. Which plants are best for you is very individual, so the only way to decide what to eat is to test things out yourself.

For more blog posts about wellness, return to the wellness series page.