As a woman, your protein needs may not match those that you hear about for the general public. Why? Because most clinical research is done on males.
The good news is that slowly, but surely, the medical community is starting to understand that women’s bodies work differently than men. This means different macronutrient, micronutrient, and activity requirements.
Whether your goal is weight loss, muscle building, or increasing your energy — protein consumption has a role to play. But it’s essential to understand your body and where you are in your life cycle to clarify your personal protein requirements so you can look and feel your best.
The amount of protein your body needs throughout your life cycle really comes down to how your body is utilizing the amino acids that you take in from your diet. While protein metabolism is often linked to muscle mass, you may be surprised to learn that protein plays a number of crucial roles in your body. What’s more, these roles become more or less important depending on your age and health status.
Here are a few of the essential roles that protein plays in your body:
#1 Enhances Lean Body Mass
Pretty much everybody wants more lean body mass and less fat mass. Why? Lean body mass burns more calories and gives you a more fit and toned body.
Your lean body mass, also known as fat-free mass, is calculated by subtracting your body fat weight from the total weight of your body. While the weight of your organs and skeletal system remains fairly consistent, the skeletal muscle aspect of your lean body mass can change from month to month or even from week to week.
This makes skeletal muscle a vital aspect of your lean body mass.
If you want to increase your metabolism, building more skeletal is one of the most well-researched ways to boost your calorie burning[*]
#2 Helps With Weight Management
Aside from its ability to boost your metabolism through increases in lean body mass, protein has some other tricks up its sleeve for weight management as well.
For instance, did you know that of the three macronutrients (protein, carbs, and fat), that protein provides the highest level of satiety? That means that compared to a blueberry muffin, a scrambled egg dish is much more likely to leave you feeling satisfied and content.
In addition, it takes more energy for your body to break down and digest protein, which raises its “thermic effect.” In other words, you actually burn more calories digesting protein than you do fat or carbs[*].
#3 Supports Immune Health
The health of your immune system is dependent on several factors in your body. Caloric malnutrition alone can have a substantial impact on how well your body defends itself, but protein, in particular, plays a crucial role in your body’s defense system.
For example, the amino acid arginine is known for its ability to enhance cellular immune mechanisms. Similarly, the presence of adequate protein in your diet is essential for T-cell function — a key immune cell[*].
In addition, in a disease state, protein breakdown from your skeletal muscle can be used to fuel your body, and particularly your immune system, to help combat whatever imbalances your body is struggling with[*].
In the United States, protein deficiency is pretty rare. The Standard American Diet (SAD) is packed with all kinds of processed and low-quality protein foods, which translates into protein sufficiency — albeit not the type of sufficiency you’re looking for.
However, if you steer clear of the SAD, you may find that your protein needs aren’t being met as sufficiently as you may think. This is especially true for active people that not only need more calories, but specifically require protein to build and maintain muscle mass. This isn’t to say that if you’re active you need to double your protein intake; just make sure you’re consuming the right ratio for your body.
- Hair loss
- Brittle/ridged nails
- Muscle loss (or inability to gain muscle)
- Impaired immunity
If you notice one or more of these symptoms, it’s possible that you could benefit from upping your protein intake. However, when it comes to malnutrition, it’s not always as cut and dry as increasing one nutrient. If any of these issues are bothering you, check in with your primary care practitioner or nutritionist for the best way forward.
Protein metabolism in both men and women throughout the life cycle remain fairly similar. There are several factors that come into play that diversify individual needs, but these don’t necessarily differ between men and women. Some examples are:
- Health status
- Activity level
- Fitness goals
However, during times of significant hormonal changes, the protein needs of men and women can look quite different. During menopause and puberty, for instance, protein needs may vary[*].
Let’s take a look at men’s vs. women’s protein needs during the life cycle.
One of the reasons that puberty becomes a time when protein needs between men and women diverge is due to the presence of the hormone testosterone. Until this time, both males and females have about the same amount of testosterone in their hormonal systems.
However, during puberty, males experience a significant increase in testosterone. Testosterone is responsible for an increase in muscle protein synthesis, resulting in increased muscle mass in males. As more protein is being used to synthesize muscle, the protein needs of pubescent boys increase as compared to females.
Some in vitro animal studies even suggest that female hormones inhibit muscle protein synthesis during this time, which would result in even lower dietary protein needs[*].
As you move away from the significant changes that puberty brings, your body continues to grow and change into young adulthood. Here it’s less a matter of hormonal changes and more a result of changing body composition.
During this time, men may still experience a faster turnover of muscle protein. This has to do with the fact that men naturally have larger muscles than women. With more muscle tissue in the body, their needs remain higher as their cells turnover and renew[*].
Does this mean that men’s muscles are naturally hungrier for protein than women?
Not necessarily. When researchers examined whether men’s muscle protein, regardless of volume, required more turnover than women, they found no differences in turnover rate[*].
Another contributor to protein turnover in your body is adiposity. Your fat cells (aka adipose tissue), is recognized as an independent endocrine organ. As such, it secretes its own hormones and inflammatory chemicals that can affect the rate of protein turnover in your body[*].
Since women tend to have a higher body fat mass than men, this could potentially affect their protein needs. However, there’s no solid evidence that this discrepancy in body composition leads to changes in dietary protein needs for men vs. women[*][*].
During menopause, a woman’s estrogen levels begin to decline as her menstrual cycle comes to an end. As a result, most women experience a progressive decrease in muscle mass as well as strength and bone density.
In fact, it’s estimated that one in three women will experience bone fractures during their post-menopausal years due to loss of muscle mass and its interplay with bone density.
In addition to the hormonal aspects of aging and muscle maintenance for women, a condition called “anabolic resistance” may also take hold[*].
Anabolic resistance results in a reduced ability for skeletal muscle to take up amino acids. For this reason, some authorities recommend increasing dietary protein intake for the post-menopausal population from the standard 0.8g/ kg to 1.0-1.2 g/kg[*][*].
As you can see, there are some clear turning points in women’s lives where protein needs may change.
In general, the guideline for protein intake is 0.8grams per kilogram of body weight. This recommendation applies to both men and women and is meant as a base recommendation[*].
Some other factors that can affect the amount of protein you need daily as a woman include activity level, age, pregnancy, and menopause. Let’s take a look at each of these in more detail.
Your activity level plays a significant role in determining the amount of protein you should consume daily. Physical activity not only increases all around caloric needs, but it also has an impact on muscle maintenance and growth — a process in which protein plays a crucial role.
To date, research has primarily focused on males, and/or both males and females when it comes to activity and protein needs. For this reason, if you’re an active woman, it’s best to go with the general guidelines and tweak for your body by paying attention to how you feel and how efficiently you’re able to gain muscle.
The general guidelines for active people are 1.2 grams of protein for each kilogram of body weight, up to 2.0 grams of protein per kilogram of body weight. Aerobic exercise requires a bit less protein, so hovering around that 1.2 grams (give or take), should be a good starting point.
Resistance training tends to require more protein, so you can potentially up your intake to 2.0 grams per kilogram if your primary activity is resistance[*].
Due to the effect of aging on muscle wasting, more research has been carried out on older populations in terms of protein needs in females. In one study, researchers concluded that for women aged 65-75 a protein intake of 1.1 grams per kilogram of body weight was the threshold of protein intake that prevented muscle loss. It should be noted that this is higher than the RDA recommendation of 0.8 grams per kilogram[*].
While 0.8 grams per kilogram is one way of calculating a baseline for protein intake, the RDA also breaks down protein needs by grams for each age group.
For women, Dietary Reference Intakes (DRI) looks like this[*]:
- Infants and children up to 9 years old are the same for boys and girls
- 9-13 years old 34 grams of protein per day
- 14-70+ years old 46 grams of protein per day
Another way of looking at protein intake is through the Acceptable Macronutrient Distribution Range (AMDR), which presents protein needs as a percentage of your daily caloric intake. For women, it looks like this[*]:
- 9-18 years old 10-30% protein
- 19-70+ years old 10-35% protein
As you can see, both the RDI and AMDR recommendations don’t leave much room for individual needs.
It should also be noted that research supports the concept that protein needs should be proportionate to body weight, and not a percentage of energy intake, The reason researchers like to push the body weight ratio is due to the crucial role that protein plays in maintaining an aging body.
For example, if you were to cut your daily calories in an effort to lose fat, you could find yourself significantly undercutting your protein needs if you were to use the percentage format. However, if you calculate your protein needs by measure of your body weight, you would ensure that your protein intake would match that of your current metabolic needs[*].
Pregnancy is a time where your protein needs increase significantly. The RDI jumps women’s protein needs up from 46 grams a day to 71 grams a day during this time. The AMDR, however, keeps protein needs between 10-35% of your daily intake[*].
As a function of body weight, the current recommendation is 0.88 grams to 1.1 grams of protein per kilogram of body weight.
Here again, it’s likely that measuring your needs based on percentage alone won’t be as accurate as taking into account your specific needs according to your body.
In addition, due to the crucial role that protein plays in creating the physical structure of your body, as well as enzyme systems and hormones, some researchers suggest that protein needs should be significantly higher than the current recommendations[*].
As mentioned earlier, menopause is a time in a woman’s life where significant shifts begin to take place in her hormonal system. These hormonal changes can result in muscle loss, and subsequently, a decline in physical performance.
Research shows women that keep their protein levels up to at least 1.1 grams per kilogram of body weight retain more lean muscle mass and superior physical function when compared with those that consume fewer grams of protein per day[*].
Protein can be found in both plants and animals; the difference is that animal sources of protein are almost always considered “complete,” whereas plant sources are rarely complete.
If you’re not familiar, a complete protein contains all of the essential amino acids in the ratio that your body needs. Consuming complete proteins on a daily basis is one of the most effective ways to keep your overall protein intake high[*].
Here is a list of complete protein sources to focus on:
- Fish (salmon, mackerel, swordfish, cod, etc.)
- Greek yogurt
- Cottage cheese
It’s easy when following a keto diet to push protein to the back burner. With all the focus on healthy fats and keeping carbs low, protein can sometimes become an afterthought.
As a woman, your protein needs differ from that of your male counterparts. This means that during your lifecycle, there will be times when keeping your protein intake high will provide numerous health benefits.
The good news is that clinical nutrition is continuing to uncover the differences between male and female protein needs. Therefore, as more research emerges, you can adjust your daily protein intake as is appropriate.
Beyond research, however, one tried, and true way to assess your health status is to pay attention to your body and its signals. If you have a suspicion that you need to up your protein intake, then take that signal and create an experiment of your own.