How much protein do I need?

What does protein do for you?

Protein's clearest job across a woman's life is protecting muscle, and it does that best when paired with strength training. Muscle responds well to training in the reproductive years, and the evidence suggests it tends to decline slowly from the mid-30s when it is not trained, a gradual and common change (Morton et al., 2018, British Journal of Sports Medicine).

The US range is a general guideline for adults, whether or not you train. Lifting helps you make the most of it, and from perimenopause onward the guidance places the range next to heavy progressive lifting.

How much protein does the evidence support?

The evidence supports a range, not a single number, and the range depends on where you live. The Dietary Guidelines for Americans, 2025–2030 put adults at 1.2–1.6 g/kg a day, which Harvard's Nutrition Source describes as 50–100% more than the previous minimum intake. In the UK, the reference nutrient intake (RNI) is about 0.75 g/kg a day for adults who are not very active, as reported by Nuffield Health.

For many women the newer US figure is less a big change than an invitation to spread protein across the day and pair it with training. Children and teens need less, and most children easily meet their figure without anyone counting; the table below gives the number for each stage.

From perimenopause onward, muscle mass and power decline, and muscle also responds less to protein and to training, a pattern called anabolic resistance (Bauer et al., 2013, PROT-AGE, and the ISSN position stands). This is a normal change, not a personal failing. The evidence supports reaching the range every day alongside heavy progressive lifting.

For the later years after menopause, the PROT-AGE position paper (Bauer et al., 2013) suggests 1.0–1.2 g/kg a day, or 1.2–1.5 g/kg for those who are active or unwell. It was written for older adults in general, so it sits beside the adult range and does not replace it. At 143 lb (65 kg), the lower range works out to 65–80 g a day. Appetite and thirst tend to fall with age, and eating enough to keep weight stable matters because weight loss in older age often means muscle and bone loss.

How much protein do I need each day, and how often?

A sensible pattern is 25–40 g at each meal across 3–4 meals, which is how the daily range is usually reached in practice. In later years, 25–30 g per meal suits many women.

If you lift, 20–40 g within about 2 hours of a session is a pattern many women find easy to keep: yogurt and fruit before, for example, or a shake after. From perimenopause onward, a small snack with protein 30–90 minutes before a heavy session, or a full meal within 2 hours after, is a sensible safeguard.

Food can cover all of this, and powder is optional. When convenience matters, the best protein powder for women is simply one that delivers 20–30 g per serving, as whey or a plant blend, ideally third-party tested (NSF Certified for Sport or Informed Sport).

Two related pages may help. For the years after menopause, our page on sarcopenia looks at muscle and aging in more depth. For girls and women who train a great deal, our page on RED-S looks at eating enough overall to match that training.

For a figure for your own weight, the protein calculator does the arithmetic. The ranges are written per kilogram, so converting from pounds first keeps things simple.

What did the studies show, and what did they leave open?

The studies show a workable range, not one exact number for every woman, and expert groups draw it in slightly different places. The International Society of Sports Nutrition position stand (Jäger et al., 2017) says 1.4–2.0 g/kg a day is sufficient for most people who exercise, a little above the US guideline range.

The groups also differ on how much to eat at one time later in life. The same position stand suggests older adults may need about 40 g in a single sitting, while PROT-AGE uses 25–30 g per meal. Either is a reasonable place to start.

The Morton et al. meta-analysis looked at protein together with resistance training, so its findings are best read with lifting in the picture. The evidence also describes groups, not individuals: your health, appetite, training and medicines all shape where you land inside a range.

Next steps

A good place to start is the row for your life stage above: pick a figure in grams, try it for a week and notice how you feel. If you lift, you might add a protein snack around your sessions. If you have a health condition, are managing appetite changes or are unsure about your numbers, a registered dietitian or your doctor can help you shape a plan. Protein is not one size fits all, so choose the range and the foods that fit your body, your training and your life.