KenDBerryMD - 5 Foods That Will SPIKE Your Insulin - 2026

Short Summary

Main recommendation: To avoid spiking insulin, especially when aiming for nutritional ketosis or intermittent fasting, watch out for five specific things: carbohydrates, excess protein, certain "healthy" foods (fruit, berries, and overcooked vegetables), bad stress, and anything that tastes sweet. The speaker presents these as the top five insulin spikers, with the first being the most obvious.

Key Points

• The five insulin spikers (as named in the video):
  1. Carbohydrates (sugar, simple starches, grains, corn, and processed foods in cardboard boxes)
  2. Too much protein
  3. Fruit, berries, and overcooked vegetables
  4. Bad stress
  5. Sweet-tasting things, even sugar-free or calorie-free ones
• The speaker says excess protein is often overlooked because many assume a low-carb diet must be high in protein, which he says is not true.
• Dr. Berry says raw fruit still spikes insulin due to its sugar, even though fiber slows absorption.
• The speaker cites a study in which participants who only swished sugar water or saccharin water in their mouths, without swallowing, still showed an insulin rise, which he calls a "cephalic insulin response."

Details Worth Noting

• Concrete instructions:
  • Avoid carbohydrates, including sugar, simple starches, grains, corn, and processed foods, if trying to achieve meaningful nutritional ketosis.
  • Do not eat too much protein if trying to stay in ketosis or intermittent fasting; the speaker says total protein needs are often overestimated, though essential amino acids are still needed.
  • Limit or leave off fruit and berries (raspberries and blueberries, for example) while aiming for ketosis, even if they are raw, organic, and fresh.
  • Eat low-glycemic vegetables like broccoli raw, lightly steamed, or lightly stir-fried so they keep some chew or crunch, rather than cooking them until mushy.
  • Reduce bad stress, such as a miserable job with a boss you dislike, while pursuing good stress like learning a skill, instrument, or sport.
  • Limit drinks and foods that taste sweet, including sugar-free and calorie-free options, if you drink them in quantity.
• The speaker says long-distance running like half and full marathons is, in his personal opinion, break-even or possibly bad stress due to repetitive strain.
• The speaker notes that raw broccoli's low glycemic index means it often won't take many people out of ketosis.
• The speaker cites a study in which participants' sweet-tasting mouth rinse, which was spat out rather than swallowed, still appeared to produce an insulin response.

Bottom Line

Insulin spikes come from more than just sugar and carbs: protein quantity, fruit, overcooked vegetables, chronic bad stress, and even the taste of sweetness can all matter, according to the speaker, so these factors are worth considering if you are trying to manage insulin levels.