Understanding and Addressing Cold Sensation on Ketogenic and Intermittent Fasting Diets

The podcast explains why individuals on ketogenic or intermittent fasting diets might experience feeling cold, attributing it primarily to insufficient heat production. This can stem from two main issues: hypothyroidism, which acts as the body's thermostat, or a perceived/actual fuel shortage. The speaker emphasizes that even in a controlled environment, feeling cold indicates a metabolic response to a lack of available energy, signaling the body is turning down its internal thermostat.

A critical distinction is made between having ample fuel reserves that are inaccessible and genuinely running low on fuel. Inaccessibility often results from insulin resistance, where the fat-storage hormone insulin locks fat within cells, preventing its use for energy. Consequently, if an insulin-resistant individual restricts calories, their body perceives starvation despite abundant fat reserves, leading to a metabolic slowdown and reduced heat production. This contrasts sharply with a fat-adapted state, where the body efficiently accesses and burns stored fat, allowing for calorie restriction without crashing metabolism or experiencing hunger.

Practical advice includes first ruling out hypothyroidism. For those experiencing coldness due to fuel inaccessibility, the recommendation is to achieve fat adaptation by consistently limiting carbohydrates (e.g., under 20 grams for a week). This enables the body to utilize its extensive fat reserves, maintaining metabolic rate and warmth. If an individual is already lean and fat-adapted but still feels cold, it suggests an actual fuel shortage, prompting the advice to increase caloric intake, potentially by spreading meals throughout the day, while still maintaining a low-carb approach.

The broader implications touch upon the evolutionary advantage of fat storage for survival during scarcity and challenge the conventional wisdom of simple calorie restriction for weight loss. The discussion highlights the importance of metabolic flexibility and understanding the body's signaling mechanisms to optimize health and well-being on low-carb or fasting protocols, moving beyond just weight loss to sustainable metabolic health and preventing unnecessary metabolic slowdown.

if you're feeling cold it's because you're not producing enough heat

your thyroid is basically your thermostat

if you have all that fuel but you can't get to it if it's locked of a way it's inaccessible this is what happens with insulin resistance

even in the midst of plenty even with an abundance of fuel reserves your body is starving

if you are trying keto and you feel cold you're probably not fat adapted yet

in ketosis you do have access to these fuel reserves and even if you start eating less your body says okay I need 2000 calories and you're only eating 1,500 no problem I know where to get it

your body doesn't care where you get the calories it doesn't care if you eat them or if the body if you can burn them from existing stores

if the body starts sensing that it's getting kind of close to the end of the fuel reserves then it's also going to cut down it's going to turn down that thermostat and you start feeling cold