The scoop on protein powders


Wednesday, 19 October 2022

Necessary? Maybe not. Can you meet protein needs instead through food? Probably.

Truth be told, many of us scoop protein powder into a smoothie at some point during the week. But how to know if you’re buying the right one and do you need it every day?

What is protein?

One of the three macronutrients, protein helps us build and repair tissues (like muscles, hair and nails), make hormones and support immune function.

Unlike its cousins, carbohydrates and fats, protein isn’t stored in the body. There is no protein reserve. We have to eat protein-rich foods each day. Think meat, fish, beans, chickpeas, nuts, yoghurt, cheese, tofu and eggs.

Animal-based proteins contain all nine essential amino acids (protein building blocks) and are called ‘complete’ proteins. Plant-based proteins are missing one or more of the essential amino acids and are classed as ‘incomplete’ proteins. So, if you’re vegetarian or vegan, eating a wide range of plant-based foods is crucial to cover all bases.

Here’s how much protein you need

Most Aussies get enough protein (often too much!). In fact, we chow through 95 kilograms of meat per year (three times the amount recommended in the Australian Dietary Guidelines).

The guidelines suggest 2.5 serves of protein per day for women and 3 for men. This is the equivalent (for men) of a 100g steak, 2 eggs and a 200g tub of yoghurt.

By the grams, the recommendations are:

Women: 0.75g per kilogram of body weight per day. For the average Australian woman weighing 72kg, this is 54 g per day.

Men: 0.84g per kilogram of body weight per day. For the average Australian man weighing 87kg, this is 73 g per day.

But, if you’re active or taller than average, you’ll need to eat a little more than this.

And for weight loss?

New research from the CSIRO supports an increase in protein intake above and beyond the guidelines for people trying to lose weight. Why? Protein-rich foods help you feel fuller for longer, creating the perfect weapon to fight off junk food cravings and overeating.

If you’re not getting enough through food, protein powders can be a good way to boost intake.

What are protein powders?

Most protein powders are based on whey, egg or a plant-based alternative such as pea, rice, hemp or soy. New to the protein powder family, cricket powder, is gaining in popularity as a sustainable option.

Hang on, wait – cricket powder?

Cricket powder, simply ground up crickets, consists of 69% protein (whey protein is 80-90%). And, being an animal source of protein has a complete amino acid profile.

Producing protein from insects generates less greenhouse gases and requires fewer resources than producing the equivalent whey protein from dairy cows. And because the flour contains the entire exoskeleton of the insect, it is also high in fibre. It’s already landed on the Australian market, found in cookies and protein bars.

Gold stars all round!

What’s the difference between whey and plant-based powders?

A by-product of cheese production, whey protein is extracted and dried to make a powder. Containing all the essential amino acids, whey is typically the go-to protein for most.

Whey concentrate is high in protein and contains low levels of fat and carbohydrate (in the form of lactose).

Whey isolate has been processed further to remove remaining fat and carbohydrates, yielding a higher percentage of protein. As isolates contain very minimal lactose, they can generally be tolerated by those with mild lactose intolerance. They are digested quicker and are more expensive, reflecting the extra processing.

As more Australians lean into a plant-based way of living, protein powder derived from plants is having a moment. But, as all plants are deficient in one or more amino acids, make sure your protein powder has a mix of plants (like rice and pea) to get the full complement of amino acids.

Ingredients to steer clear of

To reduce sugar content, most protein powders contain artificial sweeteners. Look out for these ones: Sucralose (955), Aspartame (951) or Saccharin (954). Artificial sweeteners are just that – artificial and unnecessary. Add your own sweetener to your protein powder or look for ones sweetened with stevia or honey.

Also, watch out for genetically modified soy, artificial flavours, thickeners and artificial colourings. Some of these additives can cause stomach upset and bloating.

Leave anything with claims like “fat stripping”, “shred monster”, “bulk up” on the shelf.

Check the nutrient information panel

A protein powder must contain 15-30g of protein per 100g of product. If it doesn’t, it’s not technically (or legally) a protein powder. Manufacturers must list the amount of protein per serve and per 100g so you can compare across brands.

How much protein can you absorb at once?

More protein is not better. There is a limit to how much the body can absorb and utilise at a time. So, spreading protein intake over the day is ideal. Try 4 meals a day, 3-4 hours apart.

As a rule, 25-30 grams of protein at any meal is considered best for optimal absorption. This is the equivalent to a breakfast comprised of ½ cup muesli, ½ cup yoghurt, 1 cup milk, and a handful of nuts or a 100g fillet of salmon for lunch.

Australians currently get the majority of their protein at the evening meal, although the new science suggests that a more even distribution helps hunger management and muscle metabolism.

A higher protein breakfast benefits appetite control and reduces cravings, so it makes sense to add in protein powder at breakfast, a meal that is usually lower in protein than other meals later in the day.

Different proteins absorb at different rates

Whey protein is absorbed at a rate of about 10g/hour (so it would take 2 hours to absorb a 20g serve). Whereas cooked egg protein is absorbed at a rate of 3g/hour. So, an omelette containing the same 20g of protein would take 7 hours to absorb.

Just because one is absorbed faster doesn’t mean it is better. In fact proteins that take longer to absorb may induce a more positive protein balance and help you feel fuller for even longer.

Top tip: Your body uses extra water to digest protein. So, if you're increasing your protein intake, you’ll also need to increase your fluid intake as well to avoid dehydration.

Who needs protein powders?

No one really needs protein powders to survive, nutritionally speaking. But there are some people who may benefit from supplementing with protein powder: competitive athletes, older adults, growing teenagers, people recovering from surgery or illness, and people following a vegan/vegetarian diets.

Many athletes, body builders or people trying to lose weight will use protein supplements. However, for the average gym goer, protein powders can just add unnecessary calories to the diet. Protein powder is not a magic muscle pill – you still have to work the muscles for them to grow!

And there are some downsides of too much protein. Too much can place pressure on the kidneys and increase the amount of calcium excreted in the urine, compromising bone health in the long term. Particularly those with kidney issues and who have trouble processing protein, adding in a protein powder may not be ideal. In addition, amino acids in protein powders require several vitamin and mineral cofactors for their metabolism, such as Vitamin B6, Zinc, Vitamin C and Magnesium, so taking protein powders without obtaining enough of these nutrients in the diet may compromise effectiveness.

If in doubt, consult your medical practitioner prior to adding supplementary foods to your diet.

How to use protein powder?

If you choose to use a protein powder, use it as a supplement to the diet, rather than relying on it to supply all your protein needs. It doesn’t need to be a daily affair.

Using protein powder in your food is easy:

How to get enough protein through food

When we get our protein through food, we’re getting a whole variety of micronutrients and fibre alongside the protein, just as nature intended. Including a mix of different protein sources (both plant and animal) in the diet is ideal for maximal protein absorption and balance.

(Remember, the average Australian female needs 54g per day, the average male needs 73g per day).

Source: Food Sources of Nutrients, Dr Antigone Kouris-Blazos 2011

Our picks

I use protein powder about three times per week if I know I won’t get enough protein from food that day.

I personally prefer whey protein isolate as it has the edge nutritionally. Taste wise, whey also has a more neutral taste – rice and pea can be a bit gritty and can change the taste of what you add it to.

Our picks are:

References

Food Standards Australia New Zealand (FSANZ) (2013) Sports Foods Consumption in Australia and New Zealand

Jäger, R., Kerksick, C.M., Campbell, B.I. et al. (2017). International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr 14, 20 https://doi.org/10.1186/s12970-017-0177-8

Kouris-Blazos, A. (2011) Food Sources of Nutrients

NHMRC. (2015). Australian Dietary Guidelines 1 - 5 | Eat For Health. Retrieved from https://www.eatforhealth.gov.au/guidelines/australian-dietary-guidelines-1-5

Noakes, M. (2018). CSIRO Protein Balance: New concepts for Protein in Weight Management.

OECD. (2018). OECD-FAO Agricultural Outlook 2018-2027. OECD. https://doi.org/10.1787/agr_outlook-2018-en

Schoenfeld, B. J., & Aragon, A. A. (2018). How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. Journal of the International Society of Sports Nutrition, 15(1), 10. https://doi.org/10.1186/s12970-018-0215-1

Williams, M. (2005). Dietary supplements and sports performance: amino acids. Journal of the International Society of Sports Nutrition, 2(2), 63–67. https://doi.org/10.1186/1550-2783-2-2-63

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