Potatoes are the king of carbs, but it wasn't always that way. Part of the "nightshade" family, alongside tomatoes and hot peppers, potatoes came to Europe around 1700 and quickly took dinner plates by storm.

It's hard to argue with a well prepared potato, but many health idols from Tom Brady to Paul Saladino generally avoid them. Are "inflammation" concerns around nightshades warranted?

We looked at the research, safety data, and expert perspectives (like pro-metabolic biologist Ray Peat’s) to clarify when potatoes are generally well tolerated, and when they might not be.

Why Some People Avoid Potatoes

Potatoes are nightshades, alongside tomatoes, eggplants, and peppers. These plants produce glycoalkaloids like solanine and chaconine, natural defense compounds for the plant that can irritate the gut or nervous system in humans.

This is why the Autoimmune Protocol, or AIP (an elimination strategy used to manage autoimmune disease) cuts nightshades entirely. The idea is to reduce dietary triggers that may worsen inflammation, especially in people with unresolved gut symptoms, joint pain, or immune flare-ups.

Tom Brady’s TB12 method also avoids potatoes, not because of carbs, but because of their nightshade status. His former chef has said they’re excluded to reduce joint inflammation.

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Most of these harmful chemicals reside in potato skins, however, and current domesticated breeds are far more benign today. More hard stats on this below.

Potatoes, Nightshades, and Metabolism Concerns

Ray Peat, a key figure in the pro-metabolic nutrition space, was especially cautious about foods that resist digestion or encourage gut fermentation. His concern wasn’t about allergic reactions or food poisoning, but about bacterial overgrowth, endotoxin exposure, and the long-term effects of poorly digested starch on metabolism and gut integrity.

His guidance typically included:

• Prioritizing easily digested carbs like fruit and honey
• Avoiding cold (resistant) starches and leftovers
• Minimizing plant toxins like solanine
• Peeling and thoroughly cooking starchy vegetables like potatoes

If you cook a potato (or rice) and let it cool, the resistant starch content is permanently boosted, lowering the glycemic impact and providing more fuel for gut bacteria. Reheating eliminates some, but not all of it.

Mainstream diet guidelines are enthusiastic about resistant starch, for the undeniable boost in butyrate and other beneficial SCFA's from gut bacteria, but Peat disagrees.

What the Research Says About Potato Safety

Animal studies using high doses of glycoalkaloids show gut damage, but those doses don’t reflect normal human intake. A human would have to eat several pounds of green potato skins per day to replicate those conditions.

• A 2022 trial found that 2 cups of cooked potatoes daily for 4 weeks had no measurable impact on gut barrier function (PubMed)
• Glycoalkaloid-related symptoms (like nausea) don’t typically appear unless intake exceeds 1 mg/kg body weight; a standard peeled serving delivers about 0.3 mg/kg (EFSA)

These studies don’t account for cold storage, resistant starch buildup, or individual digestion speed, all of which may affect real-world tolerance.

Resistant Starch in Potatoes: Helpful or Harmful?

When cooked and cooled, potatoes form resistant starch, a carbohydrate that bypasses digestion in the small intestine and ferments in the colon.

Mainstream view:

• Feeds beneficial bacteria
• Produces butyrate, which supports the gut lining
• Lowers blood sugar response

Ray Peat’s view:

• Fermentation can produce endotoxins
• Cold potatoes may increase bloating, brain fog, or gut irritation
• Harder to digest, especially for people with sluggish metabolism or microbiome imbalance

How resistant starch affects you mostly comes down to your digestion and gut health and biome, there's no true one-size fits all answer here.

How to Reduce Risk if You Eat Potatoes

Glycoalkaloids are mostly concentrated in the skin and eyes of potatoes, and levels increase when potatoes are exposed to light or stored in cold temperatures. Preparation and storage matter more than most people realize.

To reduce risk:

• Store potatoes in a cool, dark, dry place to prevent greening and sprouting
• Discard any that are green, sprouted, or bitter
• Peel thoroughly (this removes up to 70% of glycoalkaloids)
• Cook completely: boiling, baking, roasting, or pressure cooking are preferred
• Avoid eating potatoes cold unless you know resistant starch works well for your digestion
• If you suspect sensitivity, consider a short elimination and reintroduction

The Bottom Line on Potatoes and Nightshades

It's nearly impossible to give blanket nutrition advice for everyone, experimentation and self observation are key when making a tough call on something like nightshades.

Ultimately, in a cooked and peeled potato, the nightshade/inflammation concern is likely unwarranted, but it is possible for someone to have other issues with potatoes. Certain individuals who are hypersensitive to glycoalkaloids may be affected, but this probably isn't you.

99% of the potatoes consumed in America are drenched in hot bubbling seed oils, so if that's the case, definitely steer clear. 🫡

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