Protein’s role in women’s health has long been overlooked and underappreciated. Often celebrated as an important component to building muscle or ‘bulking up’, protein’s consumption has been largely targeted towards men. This has left women often neglecting it for fear of becoming “too muscular”. Conversely, protein can actually be a powerful ally throughout a women’s life, and this blog will highlight several reasons why.
Muscle Maintenance, not “Bulk”
A common concern of women’s regarding higher protein intakes is developing excessive muscle mass. However, building considerable muscle requires intense and specific types of resistance training, as well as high testosterone levels—a hormone that women produce in much lower quantities than men (1,2,3). Therefore, without planning and intent, the consumption of protein in women won’t automatically result in considerable muscle growth. Instead, it supports muscle mass maintenance, which naturally declines amongst women with age and accelerates during perimenopause when oestrogen levels drop (4).
Weight Management
On the topic of muscle maintenance, preserving lean muscle mass also supports metabolism (energy burned at rest). This is because lean mass burns more energy at rest than fat mass (5). As metabolic rate naturally declines with age, preserving lean muscle mass may, therefore, be an effective tool for weight management – a common challenge for women as they approach menopause (6).
Also supporting weight management, protein has what’s known as a high ‘thermic effect’, meaning your body uses a fair amount of energy in the form of calories to break it down during digestion (7,8). Moreover, because protein is digested slowly, it promotes satiety and feelings of fullness which research shows can prevent overeating throughout the day (9).
Hormonal Health
Amino acids obtained from dietary protein are the building blocks for certain hormones called peptide-hormones.
Peptide YY (PYY), glucagon-like peptide-1 (GLP-1), and Cholecystokinin (CCK), are all peptide hormones which in varying ways promote satiety and feelings of fullness. Evidence suggest their secretion is supported by the consumption of dietary protein (10,11,12,13,14).
Interestingly, Ghrelin (the hunger hormone) is also a peptide hormone, though the relationship between dietary protein and secretion of Ghrelin remains unclear. A 2019 narrative review found that, although meal consumption does suppress Ghrelin levels, this suppression is generally driven by total calorie intake rather than any specific macronutrient, and that protein’s satiating effects may not be directly linked to changes in Ghrelin levels (15).
Another hormone which protein is often touted to support the regulation of is the mood-regulating hormone, serotonin, which is made from the amino acid tryptophan. However, evidence surrounding this is also inconclusive, with some studies suggesting tryptophan cannot be converted into serotonin without carbohydrates (16,17), and even then, not enough evidence exists to show that consuming higher amounts of tryptophan-containing carbohydrates or proteins can translate to enhanced mood amongst humans.
Bone Health
As a result of diminishing oestrogen levels as women age, bone density can rapidly decline leading to an increased risk for osteoporosis (18). However, because protein can improve calcium absorption and retention, evidence suggests it may be useful in improving bone health (19), especially when paired with regular resistance training (20).
Recommended Protein Intakes
The UK’s recommended nutrient intake (RNI) for protein amongst adults is 0.75g of protein per kg of body weight per day (g/kg/day) (21). However, this recommendation is merely to meet basic physiological needs and avoid deficiencies, as opposed to optimising health and meeting the diverse needs specific to women throughout life stages or lifestyle choices.
Menopause
A recent 2024 systemic review suggests higher protein intakes of around 1.2 to 1.6g/kg/day is associated with better muscle maintenance in post-menopausal women and may be beneficial for muscle preservation in perimenopausal women too (22).
Vegans & Vegetarians
If you’re following a vegan or vegetarian diet, you may need a little more. vidence suggests an extra 10% more protein than the RNI may be needed to account for the proposed lower digestibility of plant-protein, though research is inconclusive (23,24,25).
Pregnancy
During pregnancy, The Department of Health suggest an additional 6g per day of protein above the RNI (26).
Athletes
For women engaging in regular strength training or endurance sports, multiple studies including a 2018 meta-analysis, and health organisations like The British Nutrition Foundation, suggest aiming for 1.2 and 2.0g/kg/day of protein (27,28,29,30,31,32).
*Please note, that if you have Chronic Kidney Disease (CKD), or have diabetes or hypertension and are therefore at greater risk of developing CKD, then it is suggested not to regularly exceed the RNI of protein (33).
Protein Source Considerations
Whilst there is currently no evidence to suggest there are certain protein sources more advantageous for women than for men, and vice versa, there are some things worth noting about the different options out there.
Soy
Clinical trials have shown individuals who regularly consume soy, and thus isoflavones, have significantly better bone mineral density, cognitive function, and less severe and frequent hot flushes and night sweats – a common symptom of menopause (34). This is thought to be because of a group of phytonutrients found in soy called Isoflavones.
Plant-Protein
A common fear is that plant protein is ‘incomplete’ and so each meal needs to contain ‘complementary’ protein sources to provide all essential amino acids (EAAs). However, plant proteins contain all nine EAAs. The term ‘incomplete’ comes from the fact the quantities of one or more EAA within plant foods is lower than is considered optimal. In other words they are not lacking any EAAs, some are just in lower quantities. Secondly, so long as a variety of plant-proteins are consumed throughout the day, there is no need to combine ‘complementary’ sources of plant-protein at every meal. This is because our body can pool EAAs, of which the cumulative effect should be sufficient to meet EAA requirements (35,36,37).
Protein Powder:
Whilst most people can easily meet their protein requirements via food, if you are someone who has higher needs (e.g., if you’re regularly strength training), protein powders can be a useful tool to help you meet them. If having plant-based protein powders, consider opting for either soy protein or a blend that includes brown rice protein and pea protein, as this will provide a more complete amino acid profile similar to whey protein. Furthermore, clinical trials have found these to be just as effective as whey (38,39,40,41,42).
Final Thoughts
Protein is an essential and often underestimated component of women’s health, far beyond just muscle building. As protein plays a critical role in maintaining muscle and bone mass, as well as supporting metabolism and weight management, women of all ages can benefit from making protein a priority. As dietary needs vary, especially as women move through life stages, consideration to unique lifestyles, activity levels, and dietary preferences, may be needed, along with the exploration of supplemental protein options where necessary.
Disclaimer:
Nothing in this article constitutes professional advice on which you should rely. It is provided for general information purposes only and is not a substitute for individually tailored medical advice. If you need personalised advice, please consult directly with a qualified healthcare professional.
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