The Dangers of Intermittent Fasting

What title is misleading?

When time restricted feeding can be problematic.

That title implies when to eat. His conclusion is about what to eat - protein.

Attia may be referring to this study of resistance training subjects.

Agreed. He did not refer to any study. I meant he might have been thinking of studies on muscle mass, when he gave the example of someone losing lean mass. So I searched for studies on gain or loss of muscle mass. There is, in fact a decrease in testosterone, and muscle. But there was an increase in strength, more than the no-diet group, who gained muscle.

Once can prefer more bulk (muscle), or more strength. One can also prefer fertility (testosterone) with the bulk. There are benefits for either approach.

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The IF group were doing caloric restriction, so that study can’t say anything about IF results as caloric restriction is confounding the result.

I think Layne Norton usually does a good job sharing realistic viewpoints on topics on at the apex of health science/fitness.

I guess the key question for the individual might be: Can you still get the 1.6-2g/lb LBM of protein you need in your selected feeding window. Also, keeping in mind that around 50g (debatable) seems to be close to the upper limit per meal that can be utilised for muscle protein synthesis.

150lb person eating 3 meals across 8-10 hour feeding window with each meal containing 50g protein might be a sweet spot for some. 200lb person may add 1 50g shake to this protocol (unless additional 50lb body mass is just fat mass - in which case 150g protein still likely sufficient)


This was the video that led to my unsubscribing from his channel for the second (and final) time. I will not be resubscribing. I am only interested in reliable sources try hard not to mislead.

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When I try to watch the video, it says “This video is private”. Do you know how I can watch it?

Maybe weightlifters and power athletes need 2 g per pound. But for ordinary people aged 40 to 50, to prevent sarcopenia, Mayo Clinic recommends a mere 75 to 90 grams protein.,per%20kilogram%20of%20body%20weight.

Anywhere from 10% to 35% of your calories should come from protein. So if your needs are 2,000 calories, that’s 200–700 calories from protein, or 50–175 grams. The recommended dietary allowance to prevent deficiency for an average sedentary adult is 0.8 grams per kilogram of body weight. For example, a person who weighs 165 pounds, or 75 kilograms, should consume 60 grams of protein per day.

Once you reach ages 40–50, sarcopenia, or losing muscle mass as you age, begins to set in. To prevent this and to maintain independence and quality of life, your protein needs increase to about 1–1.2 grams per kilogram or 75–90 grams per day for a 75-kilogram person

The Japanese average protein intake is below.

According to a survey conducted in 2019, men aged 15 to 19 years showed the highest daily protein consumption at around 89 grams per day on average. In contrast, the protein intake of male consumers over 80 years amounted to about 72 grams per day on average.

Paul Jaminet (Perfect Health Diet) makes the following point:

I won’t enumerate studies here, but animal studies indicate that higher carb and protein intakes promote fertility and athleticism, while restriction of carbohydrate and protein promotes longevity.

Experiments on the food preferences of insects and rodents give us clues. The paper “Macronutrient balance and lifespan,” by Simpson and Raubenheimer, cited some time ago by Dennis Mangan, summarizes evidence from animals for the influence of macronutrients on lifespan. A good example is the fruit fly; protein has the dominant effect on lifespan, with low protein favoring longevity and high protein favoring fertility. The flies eat so as to maximize fertility:

This seems to be the evolutionary preference in mammals as well as flies. When unlimited food is available, animals tend to overfeed slightly on carb and protein, sacrificing lifespan for increased fertility and athleticism.


Looks like the first video has gone private. :neutral_face:

If you search on youtube, it is still there.