Written by Vicki Ma (Accredited Practising Dietitian and Sports Dietitian)
If you think there’s no such thing as a protein overload, think again!
Take one look at the booming supplement companies, it says it all, our culture is obsessed with protein.
Why is protein so important?
Every part of our body, including the skin and muscles, among other organs, is practically made up of protein, so we need to eat protein to help build and repair these body cells. Our body breaks down protein into amino acids. There are 20 different amino acids, eight of which are essential and must come from the diet. The best sources of protein come from animal based products such as meat, fish, chicken, eggs and milk. These are considered as High Biological Valued (HBV) proteins as they contain all of the essential amino acids required by the human body. Plant based proteins such as lentils, tofu and nuts only contain some of the essential amino acids and are considered to be of Lower Biological Value (LBV). You can mix these incomplete proteins together with complete proteins to get adequate amino acid balance.
How much protein do you need?
Different people will have different protein requirements. As a general rule we need around 0.8g – 1g of protein per kilogram of body weight per day. For example, a 60kg female will need approximately 48g – 60g of protein per day. Studies have shown, the average Australian man consumes roughly 100g of protein per day, and the average Australian woman consumes around 70g a day. This is telling us we are eating far too much protein than what our body actually needs.
What foods have protein?
|1 can (95g) tuna||17g|
|2 large eggs||11g|
|1 cup (250mls) milk||8g|
|2 slices of cheese (40g)||10g|
|1 tablespoon peanut butter||4.5g|
|1 cup chickpeas||12.5g|
|1 can baked beans (220g)||11g|
What happens when you eat too much protein?
Having a high-protein diet can help curb our appetite, but having too much can also lead to weight gain. In fact, eating excess amount of calories, whether from fat, carbohydrate or protein, will lead to weight gain over time. For people with pre-existing kidney disease, eating high amount of protein (more than 2g per kg of body weight) can lead to further kidney impairment. Studies have also shown, high protein intakes can increase the amount of calcium excreted in the urine. This may put us at a higher risk of developing Osteoporosis.
Wheying up the pros and cons
Whey protein supplements are a fast and convenient way for people to get a quick dose of protein after their workout. It’s easily digested by the body and rich in branch chain amino acids (BCAAs), great for muscle resynthesis. For people who struggle with a poor appetite after exercise, shakes can be a good way to kick start the recovery process. But shakes are not necessarily better than real food. As long as you’re meeting your protein goals, there’s no evidence to suggest supplements are better for muscle growth and repair. Plus, whey protein can be very expensive and provide very little nutrients.
The take-home message
Having extra protein is not necessarily going to make your muscles grow any faster. If you eat too much protein without increasing your exercise routine, your body will simply convert this into energy and store it as body fat.
Aim to have a balanced diet with moderate amounts of protein, whole grain carbohydrates, healthy fats, fruits and plenty of vegetables. This will ensure your body meets all the nutritional requirements for overall health and well-being.
Sports Dietitians Australia. Protein Supplementation. [cited 2017 July] Available https://www.sportsdietitians.com.au/factsheets/supplements/protein-supplementation/
Australian Institute of Sport. Protein. [cited 2017 July 16]. Available http://www.ausport.gov.au/ais/nutrition/fact_sheets/protein_-_how_much
Bilsborough S, Mann N. (2006). A review of issues of dietary protein intake in humans. International journal of Sport Nutrition and exercise metabolism. 16 (2). 129 – 152.