How Much Protein Do You Actually Need?

Protein has completely stolen the spotlight over the last few years. Whether it’s influencers bragging about eating 200g a day or brands adding protein to everything from bread to cereal, it’s hard to escape chatter about the macronutrient. While some fitness content creators swear by “proteinmaxxing”, our individual needs tend to vary quite a lot, based on a wide variety of factors, including age, weight, genetics, and lifestyle. Dr. Rhonda Patrick, a biomedical scientist, has actually pushed back on the idea that more protein is always better. Speaking to neuroscientist Andrew Huberman on his Huberman Lab podcast, Patrick said that when she tried to hit the supposed goal for her weight, she felt like it was too much. Instead, she feels best eating 1.2 to 1.6g of protein per kg of body weight each day.

Of course, eating enough protein for your body and lifestyle is important, but there’s a difference between protein intake that aims to prevent deficiencies versus optimising performance or simply supporting everyday life. We spoke to two sports nutritionists to find out what protein actually does, how to know how much you need, and whether you can actually have too much protein.

What protein actually does in your body (beyond building muscle)

Protein is a macronutrient made up of amino acid chains, and it plays a key role in almost every system in the body, explains Mike Molloy, PhD, sports nutritionist and founder of M2 Performance Nutrition, which works with both elite athletes and everyday gym-goers.

“Your body uses amino acids, the building blocks of protein, to build muscle, immune cells, skin, hair, nails, connective tissue and many of the signalling molecules that keep the body functioning,” he says. As a result, protein is vital for immune function, wound healing, satiety, and healthy ageing.

Age-related muscle loss begins in our 30s, making protein goals even more essential with each passing year. “Muscle is metabolic, protective and functional,” says Molloy. “It helps with glucose control, supports strength and mobility, reduces injury risk and becomes increasingly important as we age.”

The official guidelines vs. what the latest research actually says

The recommended dietary allowance for protein is 0.8g per kg of body weight per day for adults. So if you weigh 100kg, you’d try to eat 80g of protein each day. However, this is in stark contrast to the 2g per kg that many “proteinmaxxers” swear by. So, which is correct?

The recommended dietary allowance is not wrong as such, but most people don’t realise it’s the lowest amount required to prevent deficiencies in a sedentary adult. “It’s not designed to optimise muscle mass, performance, body composition, recovery or healthy ageing,” says Molloy.

He points to a large body of modern research which recommends that active people aim for 1.6-2.2g per kg of body weight per day. Registered sports dietitian Kerri Major agrees that most people would benefit from striving to eat more than the current guidelines, advising a 1.2-2g/kg daily ballpark.

How to calculate your protein needs based on activity, age and goals

Molloy uses different tiers to determine protein intake depending on a person’s circumstances:

• For overall health, if you live an active lifestyle: 1.2-1.6g/kg/day
• If you're resistance training regularly: 1.6-2.2g/kg/day
• For fat loss while trying to preserve muscle: 1.8-2.2g/kg/day

As an example, someone who weighs 70kg and trains several times per week could aim for 120-150g of protein per day. 

However, if someone is working on lowering their body fat percentage, calculating a protein goal from their current body weight can lead to an unnecessarily high number. In that case, you're better off using a target healthy weight and calculating from there. If you’re not sure, Major recommends working with a dietitian.

How to increase your protein intake in a healthy way

If you’ve realised you aren't eating enough protein, remember to up your protein intake gradually, as this will help you avoid constipation and bloating, and spread intake across the day. “Many people eat very little protein at breakfast and lunch, then try to cram most of it into dinner,” says Molloy. “That’s not ideal for satiety, energy or muscle protein synthesis.” He recommends eating 25 to 40g of protein at each meal.

At breakfast, toast and coffee isn’t enough. Add in protein-rich foods like Greek yoghurt, eggs, cottage cheese, smoked salmon, tofu scramble, protein oats or a protein smoothie. At lunch, a salad with some chickpeas on top probably won’t cut it. Try chicken, turkey, tuna, salmon, tofu, tempeh, lentils, beans, eggs, lean beef, prawns or a higher-protein dairy option.

Don’t forget that protein should be part of a balanced diet that includes carbohydrates, fats, and fibre too, plus plenty of fluids and foods you actually enjoy. “Protein is a major pillar, but it is not the whole house,” says Molloy.

Major recommends building a meal around the protein source, then adding complex carbohydrates, fruits, vegetables, and healthy fats. “Additional protein and fibre can then be provided by incorporating foods such as beans, pulses and lentils, helping to further boost both the protein content and overall nutritional quality of the meal,” she says.

Why "proteinmaxxing" isn't for everyone

Nutrition can’t be boiled down to simple mathematical calculations. Biology and behaviour play a role. “Two people can weigh the same and have totally different protein needs depending on their age, sex, training, muscle mass, calorie intake, digestion, appetite, medical history and goals,” says Molloy.

If you’re in a calorie deficit for fat loss, you’ll need more protein than someone who is maintaining, because it helps you retain muscle while losing weight and keeps you feeling full. Older adults benefit from eating more protein because ageing muscle becomes less sensitive to the muscle-building signal from protein, Molloy explains. A professional strength athlete will, unsurprisingly, need more protein than someone whose main form of movement is walking. And someone suffering from kidney disease will also need a more cautious, medically guided approach.

“There is also the real-world side,” says Molloy. “Some people love Greek yoghurt, eggs, chicken, fish, tofu and protein shakes. Other people feel full quickly, dislike meat, have gut issues, avoid dairy or struggle to eat enough earlier in the day. The ‘best’ protein target is not just the number that looks good on paper. It is the number someone can hit consistently while still eating a balanced, enjoyable diet.”

Can you eat too much protein? What happens when you overdo it

Eating too much protein isn't a major health concern. You may hear that eating a moderately high-protein diet will damage your kidneys, but that’s an oversimplified assumption, and just not the case. “For healthy people with normal kidney function, higher-protein diets are extremely well tolerated, especially when they are paired with training and a high-quality overall diet,” says Molloy.

What tends to happen when people go down the “proteinmaxxing” route is that they prioritise protein at the expense of other nutrients, or eating more food than their body needs because they're trying to hit a "goal". They may end up eating fewer fruits, vegetables, whole grains, beans, healthy fats and carbohydrates, which can lead to lower fibre, poorer gut health, worse training performance, constipation, less dietary variety, and a worse relationship with food.

“More and more protein produces diminishing returns for muscle growth,” says Molloy. “If someone is already eating 2.2 g per kg per day of protein to support their goals, adding more and more does not magically build more muscle.”

Protein is important, but it’s not a magic fix, and it’s not everything.

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