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Casein Protein vs Whey at Night

So my go to protein powder is Whey Isolate, but is it really that much more beneficial to drink Casein protein before bed instead?

Not to any significant degree.

Okay, that’s what I was thinking but some people swear by it.

Look at what some successful people swear by, rather than just some people, and you’ll be on a good path.

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It doesn’t matter what protein you consume at night it’s what you’ve taken in daily what counts, so make sure you get all your protein needs in with all your daily meals this is much more important than what you take before bed.

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Casein Protein

The reason Casein Protein is recommended for taking before bed is that it is a a “Time Released Protein”. The digestion time of Casein is around 300 minutes., 5 hours.

Thus, during an 8 hour fast during sleeping, Casein is slowly released, feeding your muscles.

Casein is also slightly higher in the amino acid, Glutamine. Glutamine’s job is for healing and repair. Glutamine is often administered individual like burn patients for healing.

Thus, Casein is considered the “Anti-Catabolic Protein”.

Whey Protein

Whey is high in the amino acid, Leucine. Leucine turns on mTOR, Mammalian Target of Rapamycin, which is responsible for maintaining and/or increasing muscle mass.

Between 2.5 to 4.0 gram of Leucine are needed per serving (meal or protein shake) to turn on mTOR for building muscle mass. The amount of Leucine needed to turn on mTOR is age dependent.

Younger individuals need around 2.5 gram of Leucine, older individuals need about 4.0 grams.

A serving of Whey yields approximately 2.5 gram of Leucine; Whey protein is 10% Leucine. Casein protein is 8% whey.

Whey is digested in 20 to 120 minutes. The time variance depends on if you are taking a Hydrolyized Whey or something like Whey Concentrate.

Due to how fast Whey is digested, Leucine spikes mTOR, promoting muscle growth.


  1. Casein is recommended prior to bed time because it is “Time Released” during your 8 hour of fasted sleep. It feed muscle as you sleep.

Cottage and Milk are high in Casein Protein; 80% Casein and 20% Whey.

  1. Whey is recommended after a workout due to how fast it is absorbed and because it is high in Leucine, which turns on mTOR, which trigger muscle growth.

  2. Mixed Protein is optimal. It provide a quickly digested protein and a slowly digest protein. This means amino acids are supplied quickly and continue to be supplied for hour afterward.

Kenny Croxdale

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It is assessed as a slower release protein that would provides a steady stream of protein over a prolonged period. Cottage cheese contains a good amount of these proteins and is a good/alternative way to go prior to sleep.

meat also digests slowly. Food for thought.

I get the point of whey, it digests faster than wholefood protein sources so there is a theoretical advantage to it. Unless you need a shake instead of a meal, for convenience or you just don’t like eating late, there is no real benefit to it.

There was research maybe 15 years ago that showed that because Whey was so fast, and spiked insulin from the Leucine content, that 3 hours after consuming whey, muscles dumped protein out into the bloodstream as a rebound-largely in the form of glutamine which can be made from most amino acids. It was sometimes referred to as glutamine spillage. In some cases, a dose of whey followed by 6 hours of fasting lead to net negative nitrogen balance in the muscles because of the powerful rebound. Part of the rebound was due to Leucine spiking insulin which lead to rebound hypoglycemia and low blood amino acid levels on a scale of 3-5 hours which raised cortisol and made muscles release glutamine to keep blood sugar high. The real science and bro-science both said that Whey should not be the last meal of the day. In addition, since it stimulates insulin, and insulin blocks growth hormone, and growth hormone is mostly released in the first 2-4 hours of sleep, you could block your normal GH levels and cause rebound glutamine spillage at the same time.

Casien has more glutamine which is anti-catabolic and prevented the glutamine spillage effect. Leucine can be problematic because it stimulates insulin which lowers blood sugar, but Leucine is one of the only amino acids that can not be turned into glucose by gluconeogenesis.

Highly Hydrolyzed Casien by the way is just as fast absorbed as highly hydrolyzed Whey which is “very fast” but the higher glutamine and lower leucine content somewhat blunts the fast uptake and rebound, though highly hydrolyzed casien can cause rebound hypoglycemia too especially with activity. Only whole polypeptide casien could be described as a slow protein, but it would be high in glutamine and elicit only a small rise in insulin. Again, science and bro-science 15 years ago recommended whole casien before bed.

For protein to have an anabolic effect, there must be insulin, but for growth hormone release in the first 2-4 hours of sleep to be optimal, insulin should be low.

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In the end, everyone says “it doesn’t matter”.

So choose the one that tastes the best.

To me, that is the casein. It is amazing compared to the whey.

What are people’s thoughts on collagen protein powder? I’ve recently been using this mixed with whey. My typical “protein” shake, which I have for breakfast every morning:

  1. two handfuls of spinach
  2. frozen blueberries (I don’t measure, but maybe .5- 1 cups)
  3. ground flaxseed
  4. 1 scoop whey protein, which is ~20 g protein (I like plain, with minimal ingredients and no flavors)
  5. 1-2 scoops of collagen, about 12-22 g protein (also plain, unflavored)
  6. full fat kefir (also plain, no added sugar)
  7. enough whole milk to make it blendable (sometimes I use coconut water here)

I will usually have more whey protein (1-2 scoops in whole milk) immediately after weight training.

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I would never touch isolated whey and always go for slow digesting proteins. Whole milk, meat, eggs, seafood…

Well explained here:

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Thanks bro I’ll check it out

I’ve always thought that supplement companies pushed both to sell more product. Why sell only whey, when you can get a customer base to buy both whey and casein in the same transactions in the same schedule?

I’m glad Justin Harris clarified his stance on slower protein. But that being said, why not drink whey protein with added fats - like whole milk and/or peanut butter?

Who is Justin Harris? C.T. had explained why enhanced lifters can have protein running in their system 'round the clock, but drug free lifters can’t-because the RISE is amino acid levels signals protein synthesis, but without drugs that signal dies if amino acids stay constantly elevated. They have to return to normal to elicit another signal.

Also, he’s factually wrong in some of his technical details. A pound of muscle weighs 454 grams, but it only has about 90 grams of protein in it. It is about 80% water, fatty acids and glycogen.

Also, he doesn’t recognize that muscles can be loaded with fatty acids-contributing to muscle mass effectively.

On the other hand, he is right on that Whey can bring up blood sugar because over half of it is turned into glucose, but Leucine is incapable of turning into glucose directly or indirectly.

An interesting thing is that Biotest has actually been telling people to take less protein-not constantly-but in a way to spike amino acid levels 4-5 times a day.


I agree. Just because two big MF’ers make a video doesn’t mean they know what the F they are talking about. There are a lot of people with channels that are spewing BS.

I’m not saying they are wrong, but posing a vid isn’t proof.

Casein has me farting all night. I bought it because I was told it would make thicker shakes. I use the shakes as my guilt free dessert.

Some expert said going to bed with food on your stomach interfered with the release of something beneficial. I can’t remember what that something is.

Also, we are assuming that you lifted to the point to where you need the protein.

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Insulin blocks growth hormone and GH is supposed to be released in the first 2-4 hours of sleep.

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So, you’d not save carbs for end of day to aid with sleep and winding down?

My 2 cents, do whatever gives you the best sleep/makes you feel freshest next morning

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