What are high-protein diets?
Want to know why those looking to lose weight often adopt high-protein diet? Here, we tell everything you need to know about this popular approach
What is protein?
Protein is a macronutrient and essential for a number of functions including growth, brain development, healthy bones and the production of hormones. Proteins are made of ‘building blocks’ called amino acids. There are 22 amino acids needed by humans with nine termed ‘essential’ because we cannot make them in our bodies, so we have to get them from the food we eat.
We tend to divide proteins into two groups: animal and plant. Animal proteins, such as meat, cheese and eggs are sometimes referred to as ‘complete’ proteins as they contain all of these essential amino acids. Protein-rich plant foods include pulses, legumes, lentils, tofu and other soya products. As nutritious as these foods are, they are often referred to as ‘incomplete’ proteins because most of them don't contain all of the essential amino acids. However, if a plant-based diet is sufficiently varied, you should be able to hit your protein requirements.
Visit our ‘All you need to know about diets’ page for recipes and more expert advice on weight loss, including low-GI and the Mediterranean diet’
How much protein do you need?
In the UK, the Reference Nutrient Intake (RNI) is 0.75 gram/kg of body weight – this represents the minimum amount of protein you need to stay well and is based on an average, sedentary adult. As such, this is a baseline, so you need to account for additional protein needs depending on your age, weight, gender, activity levels and life stage. For more information read our expert guide on how much protein you need.
What is a high-protein diet?
High-protein diets involve eating relatively more protein, but less carbs and fat in order to support weight loss, improve energy and stabilise blood sugar levels. How you determine the amount of protein in your diet can be done by one of the following ways:
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• Calculate the absolute amount (grams) of protein in your diet
• Work out the percentage of calories derived from protein foods – there are 4kcal in each gram of protein
• Work out the amount of protein ingested per kg of body weight
How do high-protein diets work?
Including more protein in your diet is said to help suppress your appetite hormones and control your hunger for hours after you have eaten. It is also thought to improve the rate at which you burn calories, by as much as 20-35 per cent. All three of these aspects support how protein-rich diets may help you lose weight.
How to follow a high-protein diet
Following a high-protein diet is not complicated, we suggest using a nutrition app that provides protein values for different foods. This will allow you to log and track your meals, and give you an understanding of the amount of protein you are eating.
Research suggests that a diet which contributes 1.2-1.6g of protein per kg of body weight may improve appetite and body weight management. For the average, moderately active adult this equates to a target of about 25-30grams of protein at each main meal. You should ideally distribute your protein intake evenly throughout the day, including breakfast and snacks.
Have a look at our protein-rich breakfast ideas.
What foods to include on a high-protein diet?
Aim to balance complete protein sources like lean meats, fish, eggs and dairy with vegetables, fruits and other plant foods. Combining animal and plant sources of protein, like beans, pulses and nuts, helps make your diet more varied and balanced overall.
Examples of protein foods include:
- Fish
- Poultry
- Lean red meats, such as pork and venison
- Beans and pulses, such as soya
- Nuts and seeds
- Eggs
- Dairy
- Grains such as quinoa
What foods to avoid on a high-protein diet
When following a high-protein diet, it’s important to manage the amount of carbs and fat you eat. Aim to avoid foods high in sugar and refined carbs like pasta, bread and other baked goods, as well as those marketed as ‘diet’ foods. If you are eating carbs, focus on wholegrains so you benefit from the fibre and nutrients.
Fat is an essential component of a balanced diet – it plays a key role in the absorption of fat-soluble vitamins and is important for hormone, skin and nerve health. While watching your protein intake, make your main sources of fat the unsaturated variety, such as those found in oily fish, olives and avocado.
Why do high-protein diets help with weight loss?
Diets that are higher in protein are thought to help decrease hunger, increase fullness, boost the rate we burn calories and preserve muscle mass, the latter being especially important as we age. Other benefits include protecting against bone loss (when combined with bone-building nutrients, like calcium), as well as improvements to wound healing and repair.
These factors suggest a diet rich in protein may improve body composition, be effective for weight loss and help sustain your weight in the longer term.
Are high-protein diets good for you? Our nutritionist’s view…
There are certainly some stages in life when extra protein is needed, including childhood/adolescence, pregnancy, lactation, intense strength and endurance training and certain illnesses. The elderly may also require extra protein. In addition to this, many experts believe that because a diet high in carbs, refined ones in particular, is the main cause of our modern obesity epidemic, cutting back on them may be beneficial.
For the majority of people, a high-protein, low-carb diet may reduce hunger and calorie intake in the short term. For this reason, it may help with weight loss. However, researchers are still studying the long-term implications of high-protein diets, especially those that severely limit carbs. For example, studies suggest that following a low-carb diet may alter your gut microbiota, this may have a detrimental effect on the production of short-chain fatty acids (SCFAs) which play a protective role both in the gut and for your overall health.
Most health professionals believe that cutting out major food groups, such as carbs, may have an adverse effect on bone health, and on renal function for those with an existing kidney condition.
If you are interested in a high-protein diet, talk through the options with your GP, to ensure it is appropriate for you.
What are the different high-protein diets?
High-protein, low-carbohydrate diets have become increasingly popular, examples include the Atkins diet and Dukan diet. These diets typically allow you to eat unlimited amounts of meat, poultry, fish, eggs and most cheeses, while severely limiting carbs. A typical high-protein diet might consist of a breakfast of ham and eggs, lunch of cheese, meat, fish or an omelette and dinner consisting of meat or fish and vegetables.
Similarly, the paleo diet has received considerable attention for its high-protein principles. The idea behind the diet is that by sticking to an eating plan that mimics our hunter/gatherer ancestors and avoids carbs, especially grains and other modern foods, you are eating just what you need to stay lean and avoid inflammatory conditions. Another popular diet is the keto diet, this diet is slightly different because the focus is on eating higher levels of fat with more moderate amounts of protein.
Who shouldn’t follow a high-protein diet?
Diabetics and anyone with a blood sugar management issue should discuss the potential implications of a high-protein diet with their GP and healthcare team before embarking on such a regime. Similarly, anyone who meets one or more of these criteria.
- has a kidney and / or liver disease or a family history of such;
- is under 18 years old or elderly;
- has a pre-existing medical condition;
- is pregnant or breastfeeding;
- has or is recovering from an eating disorder
- or is on prescribed medication.
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Recipe inspiration
If you are concerned you're not eating enough protein, check with your doctor before changing your eating habits. If you do need to increase your intake, our delicious, nutritionist-approved recipes are perfect for a protein-boost.
High-protein recipes
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This article was last reviewed on 30 October 2023 by Kerry Torrens.
Kerry Torrens BSc. (Hons) PgCert MBANT is a Registered Nutritionist with a post graduate diploma in Personalised Nutrition & Nutritional Therapy. She is a member of the British Association for Nutrition and Lifestyle Medicine (BANT) and a member of the Guild of Food Writers. Over the last 15 years she has been a contributing author to a number of nutritional and cookery publications including Good Food
Jo Lewin is a registered nutritionist (RNutr) with the Association for Nutrition with a specialism in public health. Follow her on Twitter @nutri_jo.
All health content on goodfood.com is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. If you have any concerns about your general health, you should contact your local health care provider. See our website terms and conditions for more information.
