Protein Supplements - Whey vs. Casein

       by  Seethalakshmi Seshabhushan Nagaraja MS BS BE RDN                                                                            Published on January 29 2020 | Updated on January 29 2020

Both whey and casein are used in protein supplements – what is the difference? Did you know that both whey and casein are proteins naturally found in milk? 20% of milk protein is whey, while 80% of milk protein is casein.

Whey is digested and absorbed faster than casein. All proteins are made of amino acids. Whey and casein are good sources of the three amino acids – leucine, isoleucine and valine. These amino acids are processed quickly and muscles take up these amino acids directly. Thus, whey works quickly to protect muscles during exercise, helps with post-exercise recovery and builds stronger muscles. On the other hand, casein is also important for building strong muscles as it acts as a long-lasting source of amino acids. That glass of milk after dinner helps promote a good night’s sleep and fuels post-exercise recovery after an evening workout.

There are nine amino acids that are essential for good health. Leucine, isoleucine and valine are three such essential amino acids. We get these 9 essential amino acids from foods that are high-quality sources of protein like milk, yogurt, soy, meat and seafood.

The Recommended Daily Allowance or RDA is the average daily amount of a nutrient considered adequate to meet the needs of most healthy people.

According to the 2006 Dietary Reference Intakes - RDA1 for non-pregnant adults

Essential Amino Acid	Recommended Daily Amount mg per kg
Histidine	14
Isoleucine	19
Leucine	42
Lysine	38
Methionine	19
Phenylalanine	33
Threonine	20
Tryptophan	5
Valine	24

Note
1. The RDA is determined based on your weight. 1000 mg = 1 g
2. Consume a well-balanced nutritious diet that includes high quality protein foods to stay healthy.

According to the 2006 Dietary Reference Intakes - RDA1 for pregnant adult females

Essential Amino Acid	Recommended Daily Amount mg per kg
Histidine	18
Isoleucine	25
Leucine	56
Lysine	51
Methionine	25
Phenylalanine	44
Threonine	26
Tryptophan	7
Valine	31

Note
1. The RDA is determined based on your weight. 1000 mg = 1 g
2. Consume a well-balanced nutritious diet that includes high quality protein foods to stay healthy.

Popular natural foods that are a good source of essential amino acids

	Histidine g	Isoleucine g	Leucine g	Lysine g	Methionine g	Phenylalanine g	Threonine g	Tryptophan g	Valine g
Skim milk with vitamin A & vitamin D 1 cup or 246 g	0.248	0.448	0.854	0.743	0.093	0.168	0.166	0.048	0.222
Egg, large 1 whole egg or 50.3 g	0.142	0.31	0.528	0.418	0.21	0.332	0.299	0.083	0.369
Egg white 100 g	0.257	0.609	1.02	0.822	0.486	0.726	0.567	0.188	0.779
Cottage cheese < 0.5% fat 1 cup	0.685	1.241	2.344	1.962	0.565	1.211	1.051	0.310	1.571
Swiss cheese 1 oz	0.298	0.430	0.829	0.724	0.220	0.465	0.291	0.112	0.599
Soy milk 8 fl oz	0.149	0.279	0.456	0.321	0.066	0.277	0.265	0.093	0.287
Soy beans or edamame, frozen, prepared 1 cup	0.414	0.465	1.16	1.16	0.219	0.756	0.513	0.195	0.502
Chicken, light meat, roasted 140 g or 1 cup chopped or diced	1.18	2.10	2.85	3.23	1.05	1.51	1.6	0.444	1.88
Salmon, cooked, dry heat 3 oz or 85 g	0.643	1.01	1.78	2.01	0.647	0.85	0.958	0.245	1.13
Oat bran 1 cup	0.385	0.628	1.292	0.714	0.315	0.854	0.472	0.315	0.906
Rice, white, long grain, boiled 1 cup	0.117	0.216	0.413	0.180	0.117	0.268	0.179	0.058	0.305
Wheat bran 1 cup	0.249	0.282	0.538	0.348	0.136	0.345	0.290	0.164	0.421
Cashews raw 1 oz	0.128	0.221	0.412	0.260	0.101	0.266	0.193	0.80	0.306
Peanuts dry-roasted 1 oz or 28 nuts	0.168	0.233	0.430	0.238	0.81	0.344	0.227	0.64	0.278
Chickpeas or Garbanzo beans, boiled 1 cup	0.400	0.623	1.035	0.973	0.190	0.779	0.540	0.139	0.610
Lentils, boiled 1 cup	0.503	0.772	1.295	1.247	0.152	0.881	0.640	0.160	0.887
Moong beans, boiled 1 cup	0.414	0.600	1.099	0.990	0.170	0.858	0.465	0.154	0.735

Is there a need to rush out and buy protein supplements? Based on personal dietary recommendations, most people can get sufficient high-quality protein from natural food sources. Milk is a natural food source of high-quality protein and carbohydrate that fuels muscles. Protein supplements are definitely more expensive than milk. More research is required to evaluate if the benefits of protein supplementation vary based on gender.

With today’s busy lifestyle, many athletes and weight lifters find protein supplements are convenient to include as part of a healthy well-balanced diet. But natural foods provide synergistic benefits and vital nutrients like antioxidants that aren’t found in supplements. Nutrients found in vegetables, fruits, lentils, beans, seafood, lean meat, skim dairy products and fiber rich grains work together to help us stay healthy. So, it is important to remember that well-balanced nutrient rich natural foods are naturally superior to supplements as they promote and support overall good health. Keep in mind that even today, there are successful athletes who are vegetarians and many accomplished athletes who believe in eating healthy natural foods.

A nutritious well-balanced diet along with regular exercise and physical activity is necessary to build and maintain strong muscles. Any nutrient in excess of dietary recommendations has consequences that are not always desirable. Avoid exceeding protein recommendations when consuming protein or amino acid supplements as evolving research indicates that this could affect digestion and metabolism. Refer to the guidance of a registered dietitian nutritionist or doctor.

References
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