Macros, short for macronutrients, are protein, carbohydrate and fat: the three nutrients that supply the body with energy. [1] [2] On UK food labels each gram of protein or carbohydrate counts as 4 kcal and each gram of fat as 9 kcal. [3] Kcal is kilocalories, the calories people talk about.
UK guidance sets population shares rather than a personal ratio. [1] [4] It puts fat at no more than 35% of food energy, carbohydrate at about 50% of total energy and protein by body weight. [1] [4] Everything else you need, the vitamins and minerals, comes in small amounts and is grouped as micronutrients. [5] [2]
This article explains what each macro does and sets out the UK figures for a man in grams. It also covers where macros sit on a food label, which everyday foods carry which, and whether any of it matters for losing weight. For your own daily figures, see the macro calculator.
What does "macros" mean?
Macronutrients are the nutrients the body needs in large amounts, and the ones that provide energy. The UK government's own recommendation tables group protein, fat and carbohydrate under that heading. [1] The World Health Organization calls them the three primary sources of energy. [2]
Vitamins and minerals are the contrast, measured in milligrams and micrograms rather than grams. [5] The NHS describes them as nutrients your body needs in small amounts to work properly and stay healthy. [5] Micro means small and macro means large.
Two other things supply energy without being one of the three. Fibre is a type of carbohydrate the small intestine cannot digest, counted separately on UK labels. [3]
Alcohol carries energy too. It is not a nutrient, and UK guidance sets no intake for it, only a low-risk limit of 14 units a week. [6]
How many calories does each macro provide?
Fat carries more than twice the energy of protein or carbohydrate, gram for gram. UK labelling law fixes the conversion factors used to calculate the energy figure on every pack, in kcal and in kilojoules (kJ). [3]
| Per gram | kcal | kJ |
|---|---|---|
| Protein | 4 | 17 |
| Carbohydrate | 4 | 17 |
| Fat | 9 | 37 |
| Alcohol | 7 | 29 |
| Fibre | 2 | 8 |
Factors from the retained food information regulation, Annex XIV. [3] The NHS gives the same figures for fat, carbohydrate, protein and alcohol. It notes that alcohol's 7 kcal per gram is almost as much as fat. [7] [6]
Treat them as "about". They are conventions applied to every food, and the measured energy in a specific food varies around them.
The UN Food and Agriculture Organization's food-specific factors for protein range from 2.44 to 4.36 kcal per gram. [8] The UK food composition dataset uses 3.75 kcal per gram for carbohydrate on a different basis. [8] [9] The label figure is close enough for any decision you will make with it.
What does protein do?
Protein is what the body grows and repairs itself with. The NHS calls it essential for the body to grow and repair itself. [10] The World Health Organization describes it as the building block for muscle and for hormones and enzymes. [2]
The UK reference nutrient intake is 0.75 g of protein a day for each kilogram of body weight. [4] The government expresses that as 55.5 g a day for men aged 19 to 64. [1]
That figure relates to the general population. [1] Weight-loss trials have used more, and the reasons are set out in how much protein you need to lose weight.
Protein-rich foods are the beans, pulses, fish, eggs and meat group of the government's food-group guide, the Eatwell Guide, with dairy as a second source. [11] For a list of UK foods with the protein in each, see high-protein foods for weight loss.
What do carbohydrates do?
Carbohydrates are mainly fuel. The Scientific Advisory Committee on Nutrition (SACN) describes them as principally substrates for energy metabolism. [12] It notes that the brain, nervous system and red blood cells have an obligatory requirement for glucose. [12]
Glucose is the sugar carbohydrate breaks down into. Carbohydrate comes as starch, as sugars and as fibre.
Starchy foods such as potatoes, bread, rice and pasta are the UK's main source and also carry fibre, calcium, iron and B vitamins. [13] Gram for gram, starchy foods contain fewer than half the calories of fat. [13]
What are free sugars and fibre?
SACN recommends that free sugars make up no more than 5% of energy, which the NHS gives as 30 g a day for adults. [12] [14] Free sugars are sugars added by the manufacturer, cook or consumer, plus those in honey, syrups and fruit juice. The sugar inside whole fruit and in milk does not count. [12] [14]
Fibre is the part of plants that passes through the small intestine undigested. The NHS notes that fibre helps you feel full, which is why wholegrain versions are a good choice. [13] SACN set the adult figure at 30 g a day, and most adults eat only about 20 g. [12] [15]
What does fat do?
Fat supplies essential fatty acids the body cannot make, and it carries the fat-soluble vitamins A, D and E into the body. [7] The NHS calls a small amount of fat an essential part of a healthy, balanced diet. [7] It is also the most energy-dense macro, so the quantity matters.
UK guidance puts total fat at no more than 35% of food energy and saturated fat at no more than 11%. [1] SACN states the saturated figure as no more than about 10% of total energy, which includes alcohol. [16] The two are the same limit on different bases. [16]
The NHS puts it simply: men should not eat more than 30 g of saturated fat a day. [7]
The advice is to swap saturated fat for unsaturated fat rather than to cut fat and replace it with sugar. SACN found more evidence for replacing it with polyunsaturated fats than with monounsaturated ones. [16] The NHS adds that lower-fat products are not always lower in calories, because fat is sometimes replaced with sugar. [7]
What are the UK recommended amounts for a man?
At the government's 2,500 kcal a day figure for men, the recommendations work out as follows. [1] They are population averages. SACN says energy reference values should be used for groups and not applied to individuals, because activity and energy use vary so much between people. [17]
| Men aged 19 to 64 | UK recommendation | Basis |
|---|---|---|
| Energy | 2,500 kcal a day | Population figure, capped to address overweight [1] |
| Protein | 55.5 g a day | 0.75 g per kg of body weight [1] [4] |
| Fat | Less than 97 g | 35% of food energy [1] |
| Saturated fat | Less than 31 g | 11% of food energy [1] |
| Carbohydrate | At least 333 g | 50% of total energy [1] |
| Free sugars | Less than 33 g | 5% of energy [1] |
| Fibre | 30 g | SACN 2015 [1] |
| Salt | Less than 6 g | Government recommendation [1] |
Figures from Public Health England's 2016 summary table. [1] Women get the same percentages at 2,000 kcal, so their gram figures are lower. [1] Protein is the one figure set by body weight rather than by energy, which is why a heavier man has a higher protein figure. [4]
What does the table not say?
Two things the table does not say. It gives no protein percentage. When the fat and carbohydrate shares were set, protein was assumed to be about 15% of energy. [12]
It also sets no macro ratio for an individual. SACN's own recalculation put men's average needs at 2,605 kcal, and the government kept 2,500 because of overweight and obesity. [16]
Where does the Eatwell Guide fit?
The Eatwell Guide translates the same recommendations into food groups rather than macros. Over a day or a week, fruit and vegetables and starchy foods should each make up just over a third of what you eat. [11]
Its segments are drawn by weight of food, not by energy, so no percentage on the plate is a macro share. [18] The model behind the guide used the figures above as constraints: [18]
- Carbohydrate: at least 50% of food energy
- Fat: at most 35%
- Saturated fat: at most 11%
- Free sugars: at most 5%
- Protein: about 15%
- Fibre: 30 g
So the plate and the table are the same advice in two forms.
How do macros appear on a UK food label?
In the nutrition declaration on the back or side of the pack. By law it must show energy in kJ and kcal, then fat, saturates, carbohydrate, sugars, protein and salt. [3] [19]
The figures are always per 100 g or per 100 ml. [3] [19] Fibre is optional, and a per-portion column may be added alongside. [3]
Two readings trip people up. First, "Sugars" on a label means total sugars, not the free sugars covered by the 30 g limit. [14] Total sugars include the natural sugar in milk and fruit. [14]
Second, the "reference intake" percentages on the front are set for an average adult at 2,000 kcal, which the label must state. [3] A man's figures are usually higher.
The NHS gives the thresholds for high and low per 100 g: [19]
- Fat: high above 17.5 g and low at 3 g or less
- Saturated fat: high above 5 g
- Total sugars: high above 22.5 g
Those thresholds drive the red, amber and green colours on the front of many packs. [19] The colours cover fat, saturates, sugars and salt, never protein or carbohydrate.
Which foods are mostly which macro?
The figures below come from CoFID 2021, the UK Composition of Foods Integrated Dataset, and are given per 100 g of food. [9]
| Food (CoFID entry), per 100 g | Protein | Fat | Carbohydrate | Energy |
|---|---|---|---|---|
| Chicken breast, grilled without skin | 32.0 g | 2.2 g | 0 g | 148 kcal |
| Salmon, farmed, grilled | 24.6 g | 15.6 g | 0 g | 239 kcal |
| Eggs, boiled | 14.1 g | 9.6 g | Trace | 143 kcal |
| Cheese, Cheddar, English | 25.4 g | 34.9 g | 0.1 g | 416 kcal |
| Yogurt, Greek style, plain | 5.7 g | 10.2 g | 4.8 g | 133 kcal |
| Milk, semi-skimmed | 3.5 g | 1.7 g | 4.7 g | 46 kcal |
| Lentils, red, boiled | 8.1 g | 0.7 g | 16.9 g | 102 kcal |
| Porridge oats, unfortified | 10.9 g | 8.1 g | 70.7 g | 381 kcal |
| Bread, wholemeal | 9.4 g | 2.5 g | 42.0 g | 217 kcal |
| Rice, white, basmati, boiled | 2.8 g | 0.7 g | 26.5 g | 117 kcal |
| Potatoes, old, boiled | 1.8 g | 0.1 g | 17.5 g | 74 kcal |
| Bananas | 1.2 g | 0.1 g | 20.3 g | 81 kcal |
| Peanut butter, smooth | 22.8 g | 51.8 g | 13.1 g | 607 kcal |
| Butter, salted | 0.6 g | 82.2 g | 0.6 g | 744 kcal |
| Oil, olive | Trace | 99.9 g | 0 g | 899 kcal |
Why are most foods a mixture?
CoFID spells yoghurt "Yogurt", so the table keeps its spelling. [9]
Most foods are mixtures, and a few are close to pure. Chicken breast is nearly all protein, oil is all fat, and rice and potatoes are nearly all carbohydrate. Cheese, salmon, eggs and peanut butter carry protein and fat together, and oats and wholemeal bread carry protein and fibre alongside their carbohydrate.
In everyday talk a food is named for the nutrient that dominates it: butter is a fat, chicken breast a protein food. The British Dietetic Association applies the same logic within fats, classing butter as saturated because more than half its fat is saturated. [20] That is why counting macros means adding up every column for every food, not sorting foods into three piles.
What is the "macro diet"?
The "macro diet" is also sold as "if it fits your macros" or flexible dieting. It means setting daily targets for protein, carbohydrate and fat, and eating any foods that meet them.
None of the UK guidance cited here uses any of those names, and no UK body sets a macro ratio for individuals. [17] It is a tracking method, not a medically defined diet.
What have researchers measured?
What researchers have measured is the difference between rigid and flexible control of eating.
In a German population sample of 1,838 people and a weight programme of 54,517, rigid control went with higher BMI and more binge eating. [21] Flexible control went with lower BMI and a higher chance of successful weight loss over a year. [21] BMI is body mass index, weight in kilograms divided by height in metres squared.
In 188 women, none with obesity, rigid dieting was associated with eating disorder symptoms. [22] Flexible dieting was not. The authors note that a cross-sectional study (one that measures people once) cannot show cause. [22]
A later study of 372 men and women added intuitive eating, meaning eating by hunger and fullness rather than by rules. [23] Intuitive eating predicted lower disordered eating and less body image concern more consistently than flexible control. [23] Flexible control went with more body image concern once rigid control was allowed for, and the authors advised caution until its benefits are clearer. [23]
The fair reading is an association, not a proof. Flexible rules go with better outcomes than rigid ones in these samples, whether or not macros set the targets.
Do macros matter for losing weight?
Energy matters first, protein second and the ratio least. The NHS puts weight change down to the balance between the calories you eat and the calories your body uses. [24] [7] It notes that unused fat, carbohydrate and protein are all converted into body fat. [24] [7]
Within that, two macros earn attention. SACN found that higher intakes of sugars push up total energy intake. [12] It also found that cutting free sugars can be part of eating less for people who are overweight. [12]
Protein set by body weight is the macro with trial evidence for keeping lean mass and fullness while eating less. [25] Lean mass is muscle and other non-fat tissue. The protein article covers that evidence.
The macro calculator works your energy need out from your sex, age, height, weight and activity. It then sets protein by weight, fat within the UK ceiling and carbohydrate as the rest.
What counts is a target you can keep, checked on the scales. For a man managing his weight, that target is worth reviewing with a clinician.
Frequently asked questions
Are macros the same as calories?
No, but one gives you the other. Calories measure energy. Macros are the nutrients that carry it.
Multiply protein and carbohydrate grams by 4 and fat grams by 9 and you have most of the label's energy figure. Fibre and alcohol add the rest. Counting macros therefore counts calories as well, with the extra information of where the energy came from.
Is fibre a macro?
Fibre is a type of carbohydrate, but UK labels list it on its own line. They count it at 2 kcal per gram rather than 4. The adult target is 30 g a day, and most people eat about 20 g.
Fibre is the part of carbohydrate worth increasing when losing weight. The NHS notes it helps you feel full, which makes wholegrain versions a good choice. Track it separately if you track it at all.
Is alcohol a macro?
No. It supplies energy, at 7 kcal per gram. It is not a nutrient the body needs, and UK guidance gives it no recommended intake, only the low-risk limit below. A pint of 5% beer can carry up to 222 kcal and a 175 ml glass of 12% wine up to 158 kcal.
If you count, add the drink's calories to the day's total. The low-risk guideline is no more than 14 units a week, spread across three or more days.
Do men need different macros from women?
Not different shares, just more of each. UK guidance applies the same percentages to both sexes, at 2,500 kcal for men and 2,000 for women, so a man's gram figures are higher.
Protein is set per kilogram of body weight for both, so the difference there comes from weight, not sex.
What is a good macro split for weight loss?
No UK source sets one. The UK population figures imply roughly 50% carbohydrate, up to 35% fat and about 15% protein. SACN says those reference values are for groups, not individuals.
The practical split is protein by body weight, fat within the 35% ceiling and carbohydrate as whatever energy is left. The macro calculator applies that in grams.
Why does the label say 2,000 kcal when men need 2,500?
Because the label's reference intakes are set by law for "an average adult" at 2,000 kcal. At that level they are 70 g of fat, 260 g of carbohydrate and 50 g of protein. They are a comparison tool, not a personal target.
The government's own figures for men are 2,500 kcal, less than 97 g of fat and at least 333 g of carbohydrate. Protein is 55.5 g. Your own numbers depend on your weight, height, age and activity.
Do I have to count macros to eat well?
No. The government's consumer tool is the Eatwell Guide. It works by food groups and proportions over a day or a week, with no macro counting.
Counting for a few weeks shows you what your meals contain. If you keep one number, make it protein. It is the macro set by body weight, and the protein article covers the trial evidence.
HeMed provides clinician-led weight management. This page is general health information, not medical advice. If you are worried about symptoms, speak to your GP, or use NHS 111.
Next step: see what the HeMed blood test measures.
Sources (25)
- Public Health England, "Government Dietary Recommendations: energy and nutrients for males and females aged 1 to 18 years and 19+ years", August 2016, Table 2 (page 7) and footnotes. assets.publishing.service.gov.uk, government_dietary_recommendations.pdf. Accessed 28 October 2026.
- World Health Organization, "Healthy diet" fact sheet, 26 January 2026, sections Overview and Protein. who.int/news-room/fact-sheets/detail/healthy-diet. Accessed 28 October 2026.
- Retained Regulation (EU) No 1169/2011 on the provision of food information to consumers, as it applies in Great Britain: Annex I (definitions), Articles 30 and 32, Annex XIII Part B (reference intakes), Annex XIV (conversion factors) and Annex XV (order of the declaration). legislation.gov.uk/eur/2011/1169. Accessed 28 October 2026.
- Scientific Advisory Committee on Nutrition (SACN), "Statement on nutrition and older adults living in the community", January 2021, paragraph 4.22 and the reference nutrient intake table. gov.uk/government/publications/sacn-statement-on-nutrition-and-older-adults. Accessed 28 October 2026.
- NHS, "Vitamins and minerals", page last reviewed 3 August 2020. nhs.uk/conditions/vitamins-and-minerals. Accessed 28 October 2026.
- NHS, "Calories in alcohol", page last reviewed 12 June 2023. nhs.uk/live-well/alcohol-advice/calories-in-alcohol. Accessed 28 October 2026.
- NHS, "Fat: the facts", page last reviewed 14 April 2023. nhs.uk/live-well/eat-well/food-types/different-fats-nutrition. Accessed 28 October 2026.
- Food and Agriculture Organization of the United Nations, "Food energy: methods of analysis and conversion factors", FAO Food and Nutrition Paper 77, 2003, chapter 3. fao.org/4/y5022e/y5022e04.htm. Accessed 28 October 2026.
- Public Health England, McCance and Widdowson's The Composition of Foods Integrated Dataset 2021 (CoFID), user guide (pages 7 and 10) and sheet "1.3 Proximates" (food codes 18-323, 16-357, 12-940, 12-346, 12-555, 12-313, 13-658, 11-788, 11-981, 11-858, 13-490, 14-318, 14-892, 17-685 and 17-038), last updated 19 March 2021. gov.uk/government/publications/composition-of-foods-integrated-dataset-cofid. Accessed 28 October 2026.
- NHS, "Eating a balanced diet", page last reviewed 30 June 2026. nhs.uk/live-well/eat-well/how-to-eat-a-balanced-diet/eating-a-balanced-diet. Accessed 28 October 2026.
- NHS, "The Eatwell Guide", page last reviewed 29 November 2022, and Public Health England, "The Eatwell Guide" booklet, 2018 edition. nhs.uk/live-well/eat-well/food-guidelines-and-food-labels/the-eatwell-guide. Accessed 28 October 2026.
- Scientific Advisory Committee on Nutrition (SACN), "Carbohydrates and Health", 2015, Preface, Summary paragraphs S.15 to S.27, and paragraphs 2.17 and 11.3. assets.publishing.service.gov.uk, SACN_Carbohydrates_and_Health.pdf. Accessed 28 October 2026.
- NHS, "Starchy foods and carbohydrates", page last reviewed 15 March 2023. nhs.uk/live-well/eat-well/food-types/starchy-foods-and-carbohydrates. Accessed 28 October 2026.
- NHS, "Sugar: the facts", page last reviewed 19 May 2023. nhs.uk/live-well/eat-well/food-types/how-does-sugar-in-our-diet-affect-our-health. Accessed 28 October 2026.
- NHS, "How to get more fibre into your diet", page last reviewed 2 March 2026. nhs.uk/live-well/eat-well/digestive-health/how-to-get-more-fibre-into-your-diet. Accessed 28 October 2026.
- Scientific Advisory Committee on Nutrition (SACN), "Saturated fats and health", 2019, Summary paragraphs S.3 and S.24 with footnote 1, and Table 16.1 with footnote 7. assets.publishing.service.gov.uk, SACN_report_on_saturated_fat_and_health.pdf. Accessed 28 October 2026.
- Scientific Advisory Committee on Nutrition (SACN), "Dietary Reference Values for Energy", 2011, Preface and paragraphs 183 to 184. assets.publishing.service.gov.uk, SACN_Dietary_Reference_Values_for_Energy.pdf. Accessed 28 October 2026.
- Public Health England, "From Plate to Guide: what, why and how for the eatwell model", November 2016, Tables 2 and 5. assets.publishing.service.gov.uk, eatwell_model_guide_report.pdf. Accessed 28 October 2026.
- NHS, "Food labels", page last reviewed 30 June 2026. nhs.uk/live-well/eat-well/food-guidelines-and-food-labels/how-to-read-food-labels. Accessed 28 October 2026.
- British Dietetic Association, "Fat facts" Food Fact Sheet, December 2021 (under review). bda.uk.com/resource/fat.html. Accessed 28 October 2026.
- Westenhoefer J, Stunkard AJ, Pudel V. "Validation of the flexible and rigid control dimensions of dietary restraint". International Journal of Eating Disorders 1999;26(1):53 to 64. Abstract. pubmed.ncbi.nlm.nih.gov/10349584. Accessed 28 October 2026.
- Stewart TM, Williamson DA, White MA. "Rigid vs. flexible dieting: association with eating disorder symptoms in nonobese women". Appetite 2002;38(1):39 to 44. Abstract. doi.org/10.1006/appe.2001.0445. Accessed 28 October 2026.
- Linardon J, Mitchell S. "Rigid dietary control, flexible dietary control, and intuitive eating: evidence for their differential relationship to disordered eating and body image concerns". Eating Behaviors 2017;26:16 to 22. Abstract. doi.org/10.1016/j.eatbeh.2017.01.008. Accessed 28 October 2026.
- NHS, "Understanding calories", page last reviewed 17 April 2023. nhs.uk/live-well/healthy-weight/managing-your-weight/understanding-calories. Accessed 28 October 2026.
- Leidy HJ and colleagues. "The role of protein in weight loss and maintenance". American Journal of Clinical Nutrition 2015;101(6):1320S to 1329S. Abstract. doi.org/10.3945/ajcn.114.084038. Accessed 28 October 2026.
Numbered markers in the page text link to these entries. Statistics describe populations, not any one person’s results.
Published 28 October 2026.