How many protein shakes a day is still healthy?
Protein shakes have been popular with athletes for decades, because they contain amino acids that promote the repair of damaged muscle tissue and simultaneously stimulate the production of new muscle tissue. These days, however, protein shakes are also favoured by those who are not so intensively involved in sporting activities. Those wishing to shed a few pounds or maintain a healthy body weight for example, tend to drink one or more protein shakes per day, as they help to promote a feeling of fullness, regulate blood sugar levels and provide long-lasting energy, preventing them from indulging in unhealthy snacks between meals. Those aiming for rapid weight loss are sometimes tempted to drink multiple protein shakes per day, however this is not always recommended. In this blog you’ll learn more about the benefits of protein shakes and the maximum number that is safe to drink.
What are protein shakes?
Protein shakes are creamy drinks made from protein powder. Most protein powders on the market today contain whey (also known as milk plasma) as a primary ingredient. Whey is a by product of the cheese industry, the liquid that remains after the milk used to make cheese has been curdled. Pure, unprocessed whey boasts a fresh, slightly acidic flavour, has an extremely high nutritional value and is rich in protein, B vitamins, lactose, minerals, and beta-glucans. Whey contains little or no fat, but does contain the amino acids cysteine, glycine and glutamate, which are required by your body for the manufacture of glutathione (an antioxidant that inhibits the shortening of telomeres and thus helps to slow down the natural aging process). Whey additionally contains a substance called glutamylcysteine, a unique cysteine residue that promotes the production of glutathione (Bounous et al., 1991[1]).
An increasing number of health-conscious protein shake consumers are now opting for whole vegetable protein powders (which are usually made from hemp, brown rice or peas) instead. The key reason for choosing vegetable protein powders over whey protein powders, is that whey protein powders usually contain unhealthy additives, such as artificial sweeteners, refined sugars, soya, gluten and preservatives. You can read more about this in the informative blog: can whey protein powder be replaced with hemp protein or brown rice protein powder?. In addition, whey powders sometimes contain lactose and milk protein residues, which many are allergic to. Vegetable protein powders on the other hand, are free from allergens, don’t trigger digestive complaints and rank low on the glycaemic index. Regardless, it’s still important to vary the vegetable protein powder that you use, because repeated consumption of the same type can lead to sensitivity. After all, the more often you eat a particular food product, the greater the chance that you’ll develop an allergy to it. So, try alternating your brown rice protein powder with hemp protein powder for example.
As well as being free from unhealthy additives, vegetable protein powders boast a number of unique properties. A beneficial feature of hemp protein powder for example, is that it contains every essential amino acid and a generous quantity of minerals, enzymes and antioxidants, such as vitamin E and lecithin, both of which are important for healthy brain chemistry. Lecithin also helps to maintain a healthy liver, which in turn enhances the body’s natural cleansing process (e.g. Canty et al., 1994[2]). Hemp protein powder is additionally rich in alpha, beta and gamma globulin, which strengthen the immune system, and help to repair old and damaged tissue and create new tissue (e.g. Dwyer, 1992[3]). Furthermore, hemp protein powder contains chlorophyll and the anti-inflammatory fatty acid, G.L.A., which are known to regulate hormones and boast anti-inflammatory properties (e.g. Ziboh, 2011[4]; Hirahashi et al., 2002[5]).
Unfortunately, protein shakes made from hemp protein powder often have a somewhat ‘chalky’ texture. If you’re looking for a more palatable vegetable protein powder, then try brown rice protein powder instead. Brown rice protein powder boasts a pleasant flavour and a wonderfully smooth finish, making it a delicious ingredient in protein shakes and smoothies. An added advantage of brown rice protein powder, is that it’s more readily absorbable than hemp protein powder, and just as effective as whey protein powder in muscle recovery and muscle growth (Joy et al., 2013[6]).
Do protein shakes aid in weight loss?
Protein powders do a lot more for you body than simply accelerate muscle growth. They also encourage a feeling of fullness, regulate blood sugar levels and provide long-lasting energy, preventing you from snacking between meals and making them a valuable aid to weight loss (e.g. Westerterp-Plantenga et al., 2009[7]). And, the fact that protein powders increase muscle mass, means that you simultaneously burn more fat and lose more weight as a result. Thanks to the leucine that they contain, protein powders additionally help to prevent muscle loss – a common problem associated with high-carb weight-loss diets (Buse et al., 1975[8]).
And that's not all! Protein shakes offer countless other valuable health benefits, such as strengthening immunity, delaying the aging process and lowering blood pressure. Protein powders additionally possess anti-bacterial and anti-viral properties, and help to stabilise blood sugar levels (Petersen et al., 2009[9]). This is because the amino acid, cysteine, that protein powders contain, is converted by the body into glutathione, a powerful antioxidant that can offer relief to those suffering from cancer, HIV, hepatitis B, cardiovascular disease, osteoporosis, and bacterial infections, and accelerate recovery (Marshall, 2004[10]).
How many protein shakes a day is healthy?
Protein shakes are incredibly easy to prepare, even when you're on the go or at work. Indeed, you need simply add one scoop of protein powder to a glass, pour in water and stir. It can therefore be extremely tempting to drink numerous protein shakes per day, or to start using them as a meal replacement, particularly if you are trying to lose weight quickly. However, this is not recommended as you run the risk of missing out on important nutrients that your body requires in order to obtain sufficient energy and remain healthy. If you are not careful, it can also lead to nutritional deficiencies.
The number of protein drinks that you can safely drink in one day not only depends on how much you exercise, but also how much you weigh. Use the handy table below as a guideline:
Exercise |
Amount of protein per kilo of body weight, per day |
Little or no exercise |
0.5 - 1 gram |
Light exercise (cycling, brisk walking, light weight training, etc.) |
1.5 grams |
Moderate exercise (moderate weight training) |
2 grams |
Intensive exercise (intensive weight training, professional athletes) |
2.5 grams |
The amount of protein in your chosen brand of protein powder will be displayed on the packaging. Based on that, you can calculate the quantity of protein powder that you may safely consume per day. Whilst you can spread your protein shake intake throughout the day, you should always drink them with a meal. This means that you can therefore enjoy a maximum of 3 protein shakes per day. Never drink protein shakes during the evening, as food and drink prior to bedtime is linked to obesity. An insulin spike in the evening also prevents your immune system from making overnight use of sugars, forcing it to extract protein from muscle instead.
References
[1] Bonus, Gustavo, and Phil Gold. "The biological activity of undenatured dietary whey proteins: role of glutathione." Clin Invest Med 14.4 (1991): 296-309.
[2] Canty, David J., and Steven H. Zeisel. "Lecithin and choline in human health and disease." Nutrition reviews 52.10 (1994): 327-339.
[3] Dwyer, John M. "Manipulating the immune system with immune globulin." New England Journal of Medicine 326.2 (1992): 107-116.
[4] Ziboh, Vincent A. Gamma Linolenic Acid: Recent advances in biotechnology and clinical applications. The American Oil Chemists Society, 2001.
[5] Hirahashi, Tomohiro, et al. "Activation of the human innate immune system by Spirulina: augmentation of interferon production and NK cytotoxicity by oral administration of hot water extract of Spirulina platensis." International Immunopharmacology 2.4 (2002): 423-434.
[6] Joy, Jordan M., et al. "The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance." Nutrition journal 12.1 (2013): 1.
[7] Westerterp-Plantenga, M. S., et al. "Dietary protein, weight loss, and weight maintenance." Annual review of nutrition 29 (2009): 21-41.
[8] Buse, Maria G., and S. SANDRA Reid. "Leucine. A possible regulator of protein turnover in muscle." Journal of Clinical Investigation 56.5 (1975): 1250.
[9] Petersen, Brent L., et al. "A whey protein supplement decreases post-prandial glycemia." Nutrition Journal 8.1 (2009): 1.
[10] Keri Marshall, N. D. "Therapeutic applications of whey protein." Alternative Medicine Review 9.2 (2004): 136-156.