If you’re a woman around 50, protein requirements might not actually increase as much as you’ve been led to believe
Social media and influencers often claim that protein requirements for women increase dramatically during midlife. They suggest that a 70 kilogram woman needs around 150 grams of protein per day, which is equivalent to consuming 25 boiled eggs with 6 grams of protein each. But is this really accurate? Let’s delve into the details to find out.
Firstly, it’s important to understand what protein is and where it comes from. Protein is a crucial macro-nutrient that provides energy and helps repair and build muscles, bones, soft tissues, as well as hormones and enzymes. While we typically associate animal foods like dairy, meat, and eggs with high protein content, it’s worth noting that plant-based foods such as bread, grains, and legumes also offer valuable sources of protein.
Now, let’s consider how protein requirements change throughout different stages of life. During growth, protein requirements vary significantly, especially from infancy to young adulthood. Here are the estimated average protein requirements by age:
- 1.43g protein per kg of body weight at birth
- 1.6g protein per kg of body weight at 6–12 months (when protein needs are at their peak)
- Protein needs decline from 0.92g to 0.62g per kg of body weight from 6–18 years
Once we reach adulthood, protein requirements differentiate between men and women, reflecting the higher muscle mass typically found in men. Recommendations for individuals over 70 take into account the increased need for tissue repair and muscle maintenance. For a 70kg man, this translates to an additional 12.6g of protein per day, while for a 70kg woman, it equates to an increase of 10.5g per day. To increase protein intake by 10g, one can consume an extra 300ml of milk, 60g of cheese, 35g of chicken, 140g of lentils, or 3–4 slices of bread.
Emerging evidence suggests that higher protein intakes for individuals over 70 (up to 0.94–1.3g per kg of body weight per day) may help reduce age-related decline in muscle mass, known as sarcopenia. However, these higher intakes must be complemented with resistance-based exercises like weightlifting or using stretchy bands. It’s worth noting that these recommendations have not yet been included in any national nutrient guidelines.
Protein can be obtained from both animal and non-animal sources, providing flexibility in dietary choices.
Protein requirements and midlife
The push for higher protein intake during midlife could be attributed to efforts to prevent age-related muscle loss and potential weight gain associated with hormonal changes. However, there have been limited studies specifically examining protein intake in middle-aged women.
In a large observational study conducted in 2017, which included over 85,000 middle-aged nurses, researchers found that higher intake of vegetable protein (but not animal protein or total protein) was linked to a lower incidence of early menopause. Another study within the same group discovered that higher intake of vegetable protein was associated with a lower risk of frailty, while higher animal protein intake was linked to increased frailty risk. Total protein intake did not have a significant impact.
A smaller observational study involving 103 postmenopausal women found that those with higher protein intake had greater lean muscle mass. However, an intervention study with late postmenopausal women did not show any effect of higher protein intake on lean body mass. Some researchers hypothesize that higher protein intake, combined with reduced kilojoules (energy intake), could help reduce weight gain in menopause. Nevertheless, this theory has yet to be tested in clinical trials.
While increasing protein intake can improve satiety, leading to reduced body weight and maintained muscle mass, studies on protein intake for satiety have not specifically focused on middle-aged women but encompassed various age groups and both genders.
Current protein intake in Australia
Looking at the average daily protein intake in Australia, we can see that 99% of individuals under the age of 70 meet their protein requirements solely from food. Therefore, most adults do not require protein supplements. Only 14% of men over 70 and 4% of women over 70 do not meet their estimated average protein requirements. This could be due to various factors such as declining overall health, illness, injury, reduced appetite, limited ability to prepare meals, and the cost of animal protein sources.
While protein supplements may benefit those who don’t meet their requirements, adopting a food-first approach is generally preferred. In addition to being more enjoyable and familiar, whole foods also provide essential nutrients like iron, zinc, omega-3 fats, vitamins, and minerals. For example, red meat contains iron and zinc, fish provides omega-3 fats, eggs offer vitamin A, D, and some iron and omega-3 fats, and dairy products are a source of calcium.
If you’re concerned about your protein intake due to poor health, increased physical activity, or following a vegan or vegetarian lifestyle, it’s advisable to consult with your GP or an accredited dietitian to ensure you’re meeting your nutritional needs
