Ray Peat on Sugar

Short answer: Ray Peat argued that sugar is protective, not harmful. He wrote that sucrose and fruit lower stress hormones, support thyroid function and are less fattening than starch, and that the real dietary problems are polyunsaturated fat and excess starch.

What Ray Peat wrote about sugar

He rejected the idea that sugar causes diabetes. The belief started because diabetic urine tastes sweet, long before anyone knew the body can make sugar out of its own protein. Doctors then forbade sweets on ideology, not on evidence that it helped. Source: Sugar issues, Glucose and sucrose for diabetes

He tells the story of two 1860s doctors, Piorry in Paris and William Budd in England, who fed diabetics large amounts of sugar. One of Budd's patients got 8 ounces of white sugar and 4 ounces of honey a day, and the sugar in his urine went down. Source: Glucose and sucrose for diabetes, Sugar issues

He preferred sugar to starch. Starch and pure glucose strongly stimulate insulin, which pushes sugar into fat. Fructose restrains that insulin response, so ordinary sugar in place of starch reduces the tendency to store fat. Starch also stimulates the appetite. Source: Glycemia, starch, and sugar in context

He used the glycemic index against its own fans: orange juice and sucrose score lower than white bread or whole wheat bread. Source: Glycemia, starch, and sugar in context

He described sugar as anti-stress. Wild monkeys have low cortisol when their diet is mostly fruit, sucrose lowers the stress hormone ACTH, and he lists sugar among the things that reduce cortisol, adrenaline and free fatty acids. Source: Sugar issues, Lactate vs. CO2 in wounds, sickness, and aging; the other approach to cancer

He tied sugar to the thyroid. Turning T4 into the active T3 needs glucose, and the amount of T3 the liver makes depends mainly on how much glucose is available. Source: Glycemia, starch, and sugar in context, Glucose and sucrose for diabetes

He cites an animal experiment in which adding Coca-Cola, or the same amount of sucrose, let the animals eat 50% more calories without gaining more weight. Source: Glucose and sucrose for diabetes

He put conditions on it. Sugar is healthiest when it comes with minerals, as in milk and fruit. Refined white sugar is pure but has no nutrients, so he calls it a temporary therapeutic material or a substitute for when good fruit is not available. Source: Glucose and sucrose for diabetes, Sugar issues

What he suggested in practice

• A daily diet with two quarts of milk and a quart of orange juice gives, in his words, enough sugar for general resistance to stress. More fruit juice or honey can help under heavier stress.
• Orange juice at bedtime and before getting out of bed, because the blood becomes thicker and more clot-prone during the night.
• For hypoglycemia he names orange juice, Coca-Cola or ice cream as things that can give great relief.
• Fruit as a major part of the diet, and less starch from cereals and beans.

Where he wrote about it

This topic comes up in 62 of the articles on his site. These are the most relevant ones:

• Sugar issues · original on raypeat.com ↗
• Glycemia, starch, and sugar in context · original on raypeat.com ↗
• Glucose and sucrose for diabetes · original on raypeat.com ↗
• Phosphate, activation, and aging · original on raypeat.com ↗
• Cancer: Disorder and Energy · original on raypeat.com ↗
• Diabetes, scleroderma, oils and hormones · original on raypeat.com ↗
• TSH, temperature, pulse rate, and other indicators in hypothyroidism · original on raypeat.com ↗
• Heart and hormones · original on raypeat.com ↗

My take

This is the core of how I eat. I aim for 400 to 600 g of carbs a day, mostly simple sugars: fruit, juice, honey, Coke, table sugar. I have about 100 g of sugar with gelatin and salt in the first hour after waking.

If you are coming from keto, raise carbs slowly, 20 to 50 g per week. Your cells need time to re-learn how to burn glucose.

Quick answers

Did Ray Peat say sugar is healthy?

He wrote that sugar, especially from fruit, milk and honey, lowers stress hormones, supports thyroid function and is less fattening than starch. He also said refined sugar lacks nutrients and should be a supplement to a mineral-rich diet, not the base of it.

What did Ray Peat say about fructose?

He wrote that fructose restrains the insulin response to glucose, lowers phosphate, improves the retention of minerals such as magnesium and calcium, and he disputed the claim that fructose is to blame for fatty liver.

What did Ray Peat say about Coca-Cola?

He cites an animal study in which Coca-Cola or sucrose allowed 50% more calories without extra weight gain, and he names Coke, orange juice and ice cream as quick relief for hypoglycemia.