40+ and protein: why getting enough matters more and more with age

In our forties we start thinking more about how to keep our energy, our shape and our health for the decades ahead. In nutrition a great deal of attention goes to body weight, carbohydrates, fats and calories, but one important question sometimes stays in the background: am I getting enough protein – and can my body use it effectively?

With age, protein becomes steadily more important, above all because of one very valuable tissue: our muscle mass.

And here an important nuance comes into play. A larger amount of protein alone is not enough. If we want the amino acids from food to help preserve and build muscle tissue, the muscles also need a reason to use them.

One of the most powerful of those signals is strength training.

What happens to our muscles as we get older?

Muscle mass does not stay the same throughout life on its own. As we age, muscle mass, muscle strength and muscle function begin to decline gradually. How fast depends very much on the way a person lives – how much we move, whether we do strength training, what and how much we eat, and what our general health is like.

So a fortieth birthday does not mean the muscles start disappearing overnight. But 40+ is a very good time to start thinking of muscle mass as a long-term investment in health.

Muscles are not only there to make us look trained. They help us move, climb stairs, lift things, keep our balance and our independence, and they support the skeleton. Muscle tissue is also an important metabolic organ and one of the main places the body can direct glucose from the blood.

Preserving muscle mass therefore affects a great deal more than how we look.

With age, muscles become less sensitive to protein

After a meal containing protein, amino acids reach the bloodstream, and the body can use them among other things to build muscle protein.

In a younger body, muscle tissue responds to that rise in amino acids very well.

With age, that response can weaken. This phenomenon is called anabolic resistance.

Put simply, it means that the same small amount of protein which gave the muscle a strong building signal at a younger age may no longer produce as strong a response later in life.

That is why older adults are often advised to pay attention both to the daily amount of protein and to how much protein comes with a single meal.

This does not mean, however, that the answer is simply to eat more and more protein.

Protein gives the building material, strength training gives the order to build

Imagine that the amino acids from food are building material. You can have boards, bricks and other materials in the yard, but a house will not rise from that alone. You also need a signal telling you what to do with the material.

For muscle, one of the strongest such signals is strength training. Strength training stimulates muscle protein synthesis and makes muscle tissue more sensitive to amino acids. That is why strength training and an adequate amount of protein work best together.

• Protein provides the material.
• Strength training gives the body a reason to use that material to preserve and build muscle.

That is an important difference from the idea that preserving muscle mass is simply a matter of eating a lot of protein.

Does strength training mean we need less protein?

There is a very interesting nuance here.

It cannot quite be put that way: strength training does not automatically reduce a person’s protein requirement. Someone who trains may in fact need more protein than someone who moves little.

What studies do show ever more clearly is that once the amount of protein is already sufficient, increasing it endlessly does not necessarily bring further benefit.

A study published in 2026 involved 295 independently living older people whose average age was about 74. Over 12 weeks all participants did progressive whole-body strength training twice a week.

One group did strength training only; in the other, a protein intervention was added with the aim of reaching 1.2-1.5 grams of protein per kilogram of body weight per day.

Across the group as a whole, the additional protein brought no statistically significant benefit over strength training alone in muscle mass, strength or physical capacity.

A different result did appear among those who were getting little protein from food at the start of the study. People consuming under 1.2 g/kg – and especially under 0.8 g/kg – gained more from increasing their protein in terms of strength development.

The message is therefore not “protein is unnecessary”. The message is rather: first make sure there is enough protein, and then give the muscle a reason to use it through strength training.

Once both conditions are met, adding ever larger amounts of protein may no longer improve results at the same rate.

Why does this matter especially for women over 40?

For women, the hormonal changes of perimenopause and menopause are added in midlife to the changes that come with age.

Changing oestrogen levels affect body composition, bone tissue and metabolism among other things. Preserving muscle mass therefore becomes especially valuable at this stage of life.

In practice this means that lowering the number on the scale should not be the main goal.

A far more important question is: where is the weight loss coming from?

If we cut calories very hard, eat little protein and give the muscles no load through strength training, muscle mass may fall along with fat mass.

At 40+ we want rather the opposite: to reduce fat mass if needed, but to preserve as much muscle as possible.

This is where three important components meet: enough energy + enough protein + strength training.

How much protein might someone over 40 eat?

There is no single number that suits everyone.

Protein requirement is affected by body weight, body composition, activity, energy intake, training and state of health.

For older adults, at least about 1.0-1.2 g of protein per kilogram of body weight per day is often recommended, while higher amounts are often used for active people and those who train. The European expert group on clinical nutrition has likewise stressed the importance of combining protein with physical activity.

On the basis of the research, 1.2-1.6 g/kg per day may well be justified for active older adults, depending on the goal and the situation.

For a person of 70 kg, for example:

• 1.2 g/kg = 84 g of protein a day
• 1.4 g/kg = 98 g
• 1.6 g/kg = 112 g

If a person trains regularly with weights, or is in an energy deficit and wants to preserve muscle mass, the suitable amount may sit in the upper part of the range.

More is not automatically better, however.

Do not eat the whole day’s protein at dinner

Besides the daily total, at 40+ it is worth paying attention to how protein is spread across the day.

For many people the usual pattern looks roughly like this:

• morning – very little protein;
• lunch – a little more;
• evening – the largest amount of the day.

From the muscles’ point of view it would make more sense to give the body several proper doses of protein over the course of the day.

For older adults the scientific literature often uses about 0.4 g of protein per kilogram of body weight per meal as a guide, although the exact requirement depends on the person and on the whole day’s protein.

For a person of 70 kg that would be roughly 28 g of protein per meal.

So breakfast might have eggs with Skyr or cottage cheese, lunch fish or chicken, a snack a protein-rich dairy product, and dinner a proper protein source again.

Breakfast is especially worth a second look

Breakfast is where many people’s daily protein is weakest.

Coffee and a sandwich, porridge with a little milk, or a fruit smoothie may be perfectly decent for carbohydrates while giving very little protein.

If dinner already contains 50-60 grams of protein, adding still more there may not benefit the muscles as much as moving some of that protein to breakfast.

More recent reviews have therefore drawn attention to raising the protein content of the first meal of the day and to spreading protein more evenly.

Strength training does not only mean lifting a barbell

If the words “strength training” conjure up a heavy barbell and bodybuilding, the possibilities are in fact much broader.

Strength training means giving the muscle enough resistance that the body has to adapt to it.

For that you can use:

• gym machines;
• dumbbells and barbells;
• resistance bands;
• kettlebells;
• your own body weight;
• other resistance equipment.

What matters most is that the load is sufficient and that it progresses over time.

If you use the same light weight and the same repetitions for years, the body has no reason to get stronger.

Protein or strength training – which matters more?

There is no point in setting them against each other.

Good protein intake without giving the muscle any load leaves one very important opportunity unused.

Strength training with inadequate nutrition means in turn that we have given the body a building signal while the building material may be short.

The best result comes when nutrition and training work together.

More recent research confirms this. In a study published in 2025 with older women, strength training increased muscle protein synthesis, while leucine added to an already optimised protein intake brought no further benefit. That illustrates the principle well: once adequate nutrition is in place, the answer may not be yet more amino acids – the training stimulus given to the muscle matters too.

Where does the SmartFOOD protein package fit in?

The aim of the SmartFOOD protein package is not to teach people to eat as much protein as possible.

The aim is to make getting enough protein simple in everyday life.

The macronutrient split of the protein package is roughly:

30% protein / 30% fat / 40% carbohydrate.

That means protein makes up a considerable share of the menu, while both quality carbohydrates and the fats the body needs remain.

More important still, the protein is spread across the different meals of the day.

So there is no discovering in the evening that breakfast and lunch together came to only twenty-odd grams of protein and the whole of the rest of the day’s requirement has to be made up at dinner.

If you want to do something for your muscles at 40+, start with two things

Do not focus only on what you weigh.

Ask yourself instead: does every main meal of mine have a proper source of protein? When did I last give my muscles a reason to get stronger?

Enough protein gives the body its amino acids.

Strength training helps give the muscle the signal that those amino acids are needed to preserve, repair and build muscle tissue.

At 40+ the goal is not simply to grow older with a smaller number on the scale.

The goal might be to reach the coming decades with a body that is as strong, as functional and as metabolically active as possible.

And that investment is worth starting far earlier than we think.

Janika Koch-Mäe
nutrition adviser and personal trainer