Casein vs Whey: Should You Take Protein Before Bed?

For our overall top picks, see the Best Casein Protein in Australia guide.

For protein before bed, casein vs whey matters less than most people think: casein digests slowly and suits a night-time shake, but whey works too if your total daily protein is right. Studies show protein taken before sleep is digested overnight and used for muscle repair, but much of the benefit comes from simply eating more protein across the day. Casein is worth buying if you like a thick shake at night or find it hard to fit in enough protein. If you only want one tub in Australia, a good whey covers both jobs.

Casein vs whey at a glance

Both are complete dairy proteins. The difference is speed: in a classic 1997 study, whey raised blood amino acids quickly and briefly, while casein gave a slower, longer rise. That slow release is why brands position casein for the long gap overnight. Prices are at the time of writing.

What the research says about protein before bed

In a 2012 study by Res and colleagues, 16 young men who drank 40 g of casein after evening training and 30 minutes before sleep digested and absorbed it overnight, and their whole-body protein balance improved. A 2015 study by Snijders and colleagues found that young men who had a 27.5 g protein drink every night before bed during a 12-week training program gained more muscle size and strength than those taking a placebo. In that study the protein group also ate more protein in total, so part of the benefit is simply more protein.

A 2021 systematic review by Reis and colleagues concluded that 20 to 40 g of casein about 30 minutes before sleep improves overnight muscle protein synthesis in healthy young men, and may support gains over months of training. It also warned that uneven protein intakes between groups make the long-term results hard to judge, and that the data for older adults are limited. In short: helpful, but not magic.

The casein we stock

Both use micellar casein as their only protein, and list 600 mg (R1 Chocolate Fudge) and 540 mg (ON Chocolate Supreme) of calcium per serve. Rule 1 and Optimum Nutrition both state their casein is Informed Choice certified. Each scoop is about 120 Calories (about 500 kJ). The ON 2 lb tub weighs a little under 2 lb depending on flavour, so compare per serve.

How to use casein before bed

1. Mix one scoop (24 to 25 g of protein) with water or milk about 30 to 60 minutes before bed. Studies have used 27.5 to 40 g of protein, so some people use a scoop and a half.
2. Use less liquid and stir it with a spoon for a thick, pudding-style snack.
3. Count it towards your daily protein, rather than adding it on top of an already high intake. The ISSN suggests 1.4 to 2.0 g of protein per kg of body weight a day for most people who exercise.
4. Follow the directions on your tub, and check the label if you are sensitive to dairy.

Can you just use whey at night?

Yes. Whey digests faster, but if your total daily protein is the same, the difference in muscle gain is likely to be small. If you only want to buy one tub, a whey blend or isolate covers both post-workout and night-time shakes. A glass of milk, Greek yoghurt or cottage cheese before bed also gives you casein from food. For more on timing, read our protein timing guide, and for daily targets our how much protein per day guide.

Our verdict: casein or whey before bed?

Casein is a good fit if:

• You get hungry late at night and want a thick, filling snack.
• You struggle to hit your daily protein target with meals alone.
• You train in the evening and go to bed not long after, like the men in the Res study.

Whey is enough if you already hit your protein target, want one tub for after training and before bed, or prefer a thinner shake.

Buy casein if it suits the way you eat, not because you expect faster gains. R1 Casein and ON Gold Standard Casein are close on price per serve at the time of writing, so pick the flavour you prefer. If you would rather keep one tub in the cupboard, choose a whey such as Gold Standard 100% Whey and have a scoop at night when you need it.

Compare more options in our best casein protein guide and best protein powder guide, or browse every casein protein we stock.

How our price compares

Here is what the same products cost at other Australian supplement stores, so you can check the difference yourself.

Supps247 prices come from our website. Other prices were checked on the websites of Nutrition Warehouse, Australian Sports Nutrition (ASN), Elite Supps and Supplement Mart on 29 October 2026 (same product and size, price for one unit) and can change at any time. Sale means it was on sale that day. Not listed means we could not find that exact product on their site. Other sizes only means they sell it in a different size. Not confirmed means we could not confirm the same product and size. Supps247 members can use our Price Match Guarantee against Nutrition Warehouse, ASN, Elite Supps and Supplement Mart: we beat their full price by 5% or match their sale price (conditions apply).

Shop the products in this guide

R1 Casein 4 lb$164.95ON Gold Standard 100% Casein 4 lb$159.95R1 Casein 2 lb$84.95Gold Standard 100% Whey 5 lb$219.95

Browse all casein proteins and whey protein powders.

FAQs

Is casein better than whey before bed?

Casein digests more slowly, so it releases amino acids through the night, which is why brands suggest it before bed. Research supports protein before sleep for overnight muscle repair, but much of the long-term benefit comes from eating more protein in total. Whey at night is fine if that is what you have, as long as your daily protein target is met.

How much casein should I take before bed?

Studies have used about 27.5 to 40 g of protein before sleep, and a 2021 review described 20 to 40 g of casein about 30 minutes before bed as effective for overnight muscle protein synthesis in young men. For most people, one scoop (24 to 25 g of protein) to a scoop and a half is enough. Follow the directions on your tub.

Does casein before bed make you gain fat?

Not on its own. One scoop of R1 Casein or ON Gold Standard Casein is about 120 Calories (about 500 kJ). Fat gain depends on your total daily energy intake, not the time you have your protein. Count your night-time shake in your daily intake, and swap it for a less filling snack rather than adding it on top.

Should I take casein or whey after a workout?

Whey is the usual choice after training because it digests quickly and mixes easily, but either works when your total daily protein is right. The ISSN suggests 1.4 to 2.0 g of protein per kg of body weight a day for most people who exercise, spread across the day. Many people use whey after training and casein at night, but one tub of either is fine.

Can I get casein from food instead?

Yes. Milk protein is mostly casein, so a glass of milk, Greek yoghurt or cottage cheese before bed gives you casein from food. A casein powder is simply a convenient way to get 24 to 25 g of protein in one scoop with little fat. Choose whichever suits your diet, budget and appetite at night.

Sources: Boirie et al. 1997, slow and fast dietary proteins, PNAS; Res et al. 2012, protein ingestion before sleep, Med Sci Sports Exerc; Snijders et al. 2015, protein before sleep and training, J Nutr; Reis et al. 2021, pre-sleep protein systematic review, J Sci Med Sport; ISSN protein position stand (2017); product labels and brand nutrition panels, checked October 2026.

Order online with Australia-wide delivery, free on orders of $99.99 or more, with Afterpay available at checkout. You can also use click and collect at a store that offers it, or visit a Supps247 store in Melbourne, regional Victoria or Brisbane to compare products in person. Members can use our member price match on full-priced items.

Prices and stock were checked on 29 October 2026 and can change at any time. Always read the label and follow the directions for use. If you have a medical condition, are pregnant or take regular medication, check with your doctor first.