Weight Loss For Women: empowering health, strength and nourishment · Kitty Blomfield

#354 - The Truth About Sugar, Carbs, and Insulin Resistance: How to Transform Your Health After 40 with Issac Pohlman

September 3, 2025·55 min·4 clips

A type 1 diabetic nutritionist reversed his high A1C and low testosterone by eating carbs, not cutting them.

1. Weight Loss for Women podcast host Kitty Blankfield interviews Isaac Polman, registered dietitian and type 1 diabetic, on carbohydrates, insulin resistance, and pro-metabolic nutrition. 2. Isaac Polman is the founder of the Polman Institute, a registered dietitian with type 1 diabetes who lowered his own A1C from 9.7 to 5.6 in three months while continuing to eat carbohydrates, and co-author of the book 'Have Your Carbs and Eat Them Too.' 3. The episode's core thesis is that insulin resistance is caused by the body's inability to tolerate carbohydrates — driven by excess dietary fat and chronic stress — rather than by carbohydrate consumption itself. 4. Polman introduces 1930s-40s physician Walter Kempner's rice diet, in which patients eating 95% carbohydrates with very low fat reversed kidney failure, obesity, and diabetes — directly contradicting the assumption that carbohydrates drive blood sugar disease. 5. The mechanism Polman cites is the Randall cycle: as fat in the diet or bloodstream increases, carbohydrate tolerance decreases; Kempner's low-fat diet reversed insulin resistance by improving carb tolerance through this seesaw relationship. 6. Cortisol blocks insulin's ability to move glucose into cells, and under chronic stress the body releases fat into the bloodstream — both effects further lower carbohydrate tolerance via the Randall cycle. 7. Chronic stress causes four compounding harms to blood sugar: insulin resistance, reduced carb tolerance, muscle loss that removes glycogen storage capacity, and depletion of water-soluble minerals — sodium, potassium, magnesium, calcium, B vitamins — through stress-driven urination. 8. Polman acknowledges that low-carb diets produce genuine short-term benefits via stress hormone activation: energy, focus, appetite suppression, and weight loss — explaining their initial appeal. 9. Long-term low-carb diets cause the body to exhaust its stress hormone reserves, leading to deeper insulin resistance, chronic fatigue, muscle loss, and eventual inability to perform the workouts that originally felt energizing. 10. Carbohydrates are 'one of the most anti-stress substances we have,' Polman argues, because glycogen stored in the liver reduces the body's need to release cortisol to break down muscle or fat for energy. 11. The liver requires carbohydrate energy to convert inactive thyroid hormones to their active form — a process Polman compares to ripping the safety seal off a supplement bottle; without that conversion, thyroid hormone cannot govern cellular health. 12. Active thyroid hormone affects every cell: mental health, stress, mood, sleep, digestion, energy, A1C, blood sugar, insulin, blood pressure, cholesterol, and other hormones — making carbohydrate intake central to whole-body function, not just blood sugar. 13. Polman addresses CGM-driven fear of post-meal blood sugar rises, using a direct analogy: elevated heart rate during exercise is not a cardiovascular disease signal, and blood sugar rising after meals is an equally normal, purposeful physiological response. 14. Women who chase flat CGM blood sugar lines often develop hypothyroidism, fatigue, hair loss, and lost menstrual cycles — and Polman says doctors are prescribing thyroid medication to patients who actually need more carbohydrate nourishment. 15. Fructose — found in fruit, root vegetables, and sweet-tasting foods — is better tolerated than starch-based glucose for people with insulin resistance because it is absorbed directly into the liver via an insulin-independent pathway, bypassing the damaged insulin signaling cascade. 16. Potassium, needed at approximately 4,800 mg per day, has insulin-like properties (citing Ray Peat) that pull glucose into cells; it is widely deficient, and stress depletes it further through urination — requiring both dietary sourcing and stress reduction. 17. Polman uses a 'leaky bucket' analogy: eating potassium-rich foods like oranges and potatoes without addressing chronic stress is futile because the nutrients drain away before they can work. 18. Blankfield and Polman both describe the pattern of pro-metabolic newcomers gaining 30-60 pounds by overcorrecting from restriction to unrestricted high-fat, high-carb eating without calorie awareness or muscle-building foundations. 19. People drawn to metabolic science, thyroid health, insulin resistance, or the 'pro-metabolic' nutrition space who want a mechanistic explanation of why low-carb diets fail long-term will find this episode directly useful. 20. Listeners who prefer a purely dietary-restriction framework, or who are looking for weight-loss protocols rather than metabolic restoration, are likely to find the episode's emphasis on eating more and starting slowly counterintuitive.

As heard by us

A plainspoken, pro-carbohydrate discussion that keeps blood sugar in view without getting too technical.

The episode is a straightforward, pro-carbohydrate discussion between Kitty Blankfield and Isaac Polman, a type 1 diabetic nutritionist and founder of the Polman Institute.

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Why you'd press play

You want a no-panic carb reset from a type 1 diabetic nutritionist.

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