In a previous post, Atkins Diet: Common Errors, I commented on butter’s unusual ability to provoke insulin responses. I offer this as a possible reason why, after a period of effective weight loss on a low-carbohydrate program, inclusion of some foods, such as butter, will trigger weight gain or stall weight loss efforts.
This develops because of butter’s insulin-triggering effect, doubling or tripling insulin responses (postprandial area-under-the-curve). If insulin is triggered, fat gain follows.
Here’s one such study documenting this effect: Distinctive postprandial modulation of ß cell function and insulin sensitivity by dietary fats: monounsaturated compared with saturated fatty acids
López et al 2008
From Lopez et al 2008. Mean (± SD) plasma glucose, insulin, triglyceride, and free fatty acid (FFA) concentrations during glucose and triglyceride tolerance test meal (GTTTM) with no fat (control), enriched in monounsaturated fatty acids (MUFAs) from refined olive oil (ROO meal), with added butter, with a mixture of vegetable and fish oils (VEFO) or with high-palmitic sunflower oil (HPSO). N = 14.
The postprandial (after-eating) area-under-the-curve is substantially greater when butter is included in the mixed composition meal. This effect is not unique to butter, but is shared by most other dairy products.
Fat, in general, does not make you fat. But butter makes you fat.
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I’m stunned by your absolute condemnation of butter based on this one study. Geez, have you been paid off by Wesson or Crisco? You need to consider all the confounding variables in this study. Your blog post should be retracted and/or rewritten. This is very disappointing after your carefully researched examination of wheat.
In my experience, butter and butter fat are good for you. I have lost considerable body fat and gained much muscle this year on an eating plan that involves a lot of raw milk and cream from grass-fed cows, 3 to 4 glasses of milk and up to a cup of cream per day. Butter fat is not making ME fat, quite the opposite.
Insulin goes down faster because the vegetable fats are stored in the fat tissue faster..
A better understanding of butter is here :
http://high-fat-nutrition.blogspot.com/2012/09/protons-pancreas.html
There is another problem with that study – people do not keto adapt in 8 hours – it takes 4- 6 weeks to fully adapt to a low carb diet.
Once adapted, low-carbers are BETTER able to clear FA as the liver revs up it’s fat metabolic capabilities. Low carbers also tend to eat less frequently – reducing the exposure to both BG and FA – only when both are elevated do we see the pronounced toxic effects of the fats.