Nutritionist Sarah Di Lorenzo: Signs you’re not getting enough protein or similar and how much is too much?

Protein is one of our three macronutrients and essential for life but it is important to know how much is too much and when you are not getting enough.

Even though protein is really having a moment now, knowing the right amount for your optimal health is key.

But first, let’s explain what protein actually is. Protein is the building-block nutrient of our body. It makes up your muscles, organs, skin, hair, immune cells, enzymes and hormones. It is essential for healing, strength and metabolic health.

We are constantly breaking down and rebuilding tissues. Protein provides the amino acids to do that repair work. It also helps keep you full, supports immunity, hormones, neurotransmitters, enzymes, bone, fluid balance, transport, stabilises blood sugar and supports healthy ageing.

As a clinical nutritionist, I often see people who are not eating enough protein. for lots of different reasons. You might notice you’re losing muscle rather than fat when your weight drops, or you feel weaker climbing stairs or exercising. If clothes feel looser around the thighs and bottom, but your waist doesn’t change much, this is a clue that you’re losing lean tissue, not just fat, but this also depends on your age. Many people also report feeling tired and exhausted in the afternoon, moody, irritable, brain fog, and hungry again soon after meals, especially if those meals are mostly carbohydrate.

Hair, skin and nails are another giveaway — this would be the first sign of low protein in the diet. It can show up as more hair shedding than usual. You will notice this in the shower when washing hair, on clothing and when brushing. Weaker nails that are brittle, peel or split as well as skin that looks dull, thin or slow to heal after minor cuts or any procedures, are other signs.

We need protein for our immunity and wound healing. When protein is low wounds, bruises or surgical scars may take longer to repair. Some people also notice more frequent infections, as antibodies and many immune factors are protein-based.

If you’re doing resistance training, exercising a lot or playing sport and find you are not recovering well, you may have persistent soreness, plateaus in strength, or feeling wiped out after sessions then I would suggest monitoring your protein intake as something I would first assess.

How much protein you actually need depends on age, body size, health status and activity.

For a generally healthy adult, my guideline is around 1–1.2 g per kilogram of body weight per day, and higher — often 1.2–1.6 g/kg — if you are over 50, physically active, trying to lose fat while preserving muscle or recovering from illness or surgery.

We need to have a good source of protein at every meal and most snacks. For example eggs, fish, poultry, meat, tofu, tempeh, legumes, Greek or coconut yoghurt, good quality protein powders, nuts and seeds.

People often ask whether you can ever eat too much protein. In a healthy person with normal kidney and liver function, a high-protein diet within reason is usually safe.

A high protein intake would be around 2g/kg per day. This is what I recommend to my patients who are body builders. There is research that shows athletes and older adults can have a high protein intake without harming kidney function when the kidneys are healthy to begin with.

The body is quite good at using protein for tissue building, immune function and hormone production and what is not used will then convert any excess amino acids into energy but if that energy is not needed then it is stored as fat.

While protein is so important, more is not better. Very high intakes can crowd out other important nutrients if your plate becomes all protein and very little vegetables, whole grains or healthy fats that can lead to being malnourished. It can also lead to constipation and dehydration. Long-term, this means you’re missing out on fibre, antioxidants and beneficial plant compounds that protect your gut, heart and metabolic health.

For those of you who already have reduced kidney function, advanced liver disease or certain metabolic conditions, then excess protein can be dangerous, so always check with your doctor if this is you.

It’s also worth being mindful of where the protein comes from. It is important to avoid processed meats and high-saturated-fat cuts are very different, from a health perspective, to fish, meat, legumes or tofu.

I recommend distributing protein evenly across the day rather than piling it all into one meal so you giving your body a constant protein supply. Aim for roughly 20–30g at breakfast, lunch and dinner, and topping up with smaller protein-rich snacks. This will support muscle, hormones and satiety far more effectively than a low-protein day followed by a huge steak at night.

If you recognise some of the low-protein signs in yourself such as poor recovery, hair loss, and feeling weak, then I suggest tracking your intake for a few days then adjusting with the guidance of a qualified professional, especially if you also have kidney, liver or thyroid issues.

Find the power

Sarah has just launched her own range of protein powders which have up to 25g of protein per serve and a 5-star health rating. 10:10 Protein Powder flavours Vanilla Kiss, Natural and Choc Fudge flavours are available from her website sarahdilorenzo.com