Updated: Jul 1
There is a good chance the answer is no. ‘No’ because many of my clients (meat eating and plant-based) aren’t eating enough protein and a 2011-12 Australian Healthy Survey regarding dietary protein consumption confirms what I see in clinic - only 14% of Australians are attaining the recommended daily intake (RDI) for dietary protein. What’s more, the figure is likely to be worse among females. These numbers are frightening!
How Much is Enough?
When you understand that the RDI of .75g/kg of body weight for females and .85g/kg for men was established just to avoid protein deficiency and is currently in a state of review, it’s even more frightening.
According to the The International Society of Sports Nutrition inactive females should consume about 1g/kg of body weight, which means for an inactive female weighing 60kg the amount of protein required to achieve this goal would be 60g / day. Based on the evidence and International Society of Sports Nutrition recommendations, in clinic I increase this to as much as 1.8g/kg of weight for females who are training, needing to lose weight or heal from bone or soft tissue injury. The numbers are higher again for men. Keep reading for more on how these numbers can be achieved.
What is Protein?
Protein is one of the three macronutrients (the others being carbohydrate and fat) and its’ role is to provide the building blocks of the body – these building blocks are otherwise known as amino acids. There are 20 different amino acids.
The amino acids within protein are required for:
Muscle growth, recovery, repair & maintenance
Healthy joints, tendons, skin, hair, nails, bones, skin & blood vessels
The production of hormones and neurotransmitters
Contrary to popular belief, protein isn’t just about building muscle. Every cell of the human body requires protein to function optimally.
Protein and amino acids are crucial to:
Cognition & mood
Training, performance & recovery
Defending against inflammation
Defending against bone or join related conditions
Fertility & lactation
Let’s dial in on a few of those points:
1. Metabolism and Weight Management
Meta-analysis and large well-controlled clinical trials have shown that high protein, low carbohydrate dietary strategies are associated with positive impacts on weight reduction and maintenance, energy expenditure and a range of metabolic disease risk factors. There are many possible mechanisms by which protein supports metabolic health and weight management, with the most likely being:
Better appetite control due to increases in appetite controlling hormones
More stable blood glucose levels
Increased diet-induced thermogenesis, which essentially means that compared to other macronutrients, protein demands more energy for digestion
It helps to build muscle, in turn contributing to an increase in resting metabolic rate meaning more energy can be burned at a rest state
For anyone looking to improve this area of their health, the best effects are seen when protein intake is at or above 25% of total energy intake. For a female consuming 1600 calories per day, to achieve 25%, 100g protein would need to be consumed.
2. Growth and Development in Key Stages of Life
Protein is considered vital to in utero, infant and childhood growth and development. Furthermore, suboptimal protein intake during pregnancy and lactation has been shown to have negative consequences on the growth and development of the infant in the short- and long-term.
3. Bone & Joint Health
The quality and quantity of protein intake also has an important impact on calcium regulation in bone. Optimising quality protein intake not only provides the foundations for bone growth, but also supports calcium absorption and in turn, bone mineral content.
Dietary Protein Goals
Of the 20 different amino acids nine are considered essential. There are what we refer to as ‘complete sources’ of proteins, which contain all essential amino acids and ‘incomplete sources’, which contain some but not all of the essential amino acids. Animal proteins are naturally a complete source of protein. On a plant-based diet, while tempeh, tofu, quinoa and hemp are considered complete protein sources, for variety sake, they can’t be the only source of protein. So, those on a plant-based diet should be particularly conscious of consuming a variety of plant-based protein sources to obtain the required amount of essential amino acids.
Below are protein sources (plant and animal) in 20g equivalents:
Organic, non-GMO tempeh: ~120g
Organic, non-GMO form tofu: ~120g
Cooked lentils or beans: ~1 cup
Cooked quinoa: ~2 cups
Beef or lamb: ~120g
Chicken, turkey or fish: ~120g
Whole eggs: ~3 eggs
Protein powder (pea & rice blend): 20g equivalent (check the packet for servings)
Cooked lentils or beans (1/2 cup) and hemp seeds (3 tbsp)
Additionally, protein can be found in nuts, including but not limited to almonds, walnuts, cashews and their respective butters and seeds, including chia, hemp and hemp powder, flax, sunflower and sesame.
Below is an example of how an active female weighing 60kg's might achieve adequate protein in a day using plant-foods only:
Meal 1: Calcium Rich Raspberry Smoothie
Meal 2: Vegan Omelette
Meal 3: Gooey Veg Ragu
A few Considerations for Protein Intake:
Requirements are very much relative to age, gender, whether you’re pregnant or breast feeding, how much & what type of training is being done and broader health goals. So, please make sure you seek tailored advice if you really want to understand your unique requirements.
Don’t eat all of your protein in one meal, servings should be kept to 30 - 40g at a time.
If you exercise, you absolutely have to eat protein after training to support muscle protein synthesis. Whether you choose to eat it before or during is very much relative to your goals.
This article doesn't explore the requirements for specific amino acids, but this is certainly something that you should discuss with a practitioner if you need support with body fat loss, training nutrition, injury recovery or plant-based eating.
Digestive capacity impacts protein break-down and amino acid availability so if you have any digestive complaints please be sure to seek tailored advice.
I hope this has helped you to understand whether or not you're eating enough protein. If you'd like tailored advice regarding your day to day or training nutrition needs then I'd love to work with you. Feel welcome to book a Complimentary 15-minute Discovery Call to get started.
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