You could spend your whole life reading about all the ways you can go about losing weight, but it really boils down to one thing – you need to burn more calories than you consume. But to make sure you’re doing that you have to have a rough idea of the calories you’re burning and the calories you’re consuming, which leads us to the art of calorie counting.
You can count calories more easily than ever thanks to dedicated apps, as well as fitness trackers that do some of the work for you, but you can’t rely on them to do everything. For more information on calorie counting we spoke to dietitian Lucy Perrow, speaking on behalf of the British Dietetic Association.
How many calories should people eat in a day?
This depends on numerous factors – gender, height, weight, amount and type of activity, metabolism, genetics. The guidelines for recommended daily calorie intake is 2,000 calories a day for women and 2,500 for men, but this is very general and I would usually recommend people calculating their own requirements.
How do you calculate your calorie requirement?
The Basal Metabolic Rate (BMR) is the amount of energy – calories – your body needs while resting. This accounts for about 60 to 70% of calories burned in a day. In general, men have a higher BMR than women. One of the most accurate methods of estimating your basal metabolic rate is the Harris-Benedict formula:
Adult male: 66.5 + (13.75 x weight in kg) + (5.003 x height in cm) – (6.755 x age in years) = BMR
Adult female: 65.51 + (9.563 x weight in kg) + (1.850 x height in cm) – (4.676 x age in years) = BMR
To determine your total daily calorie needs, multiply your BMR by the appropriate activity factor that most closely matches your activity level:
- If you are sedentary (little or no exercise): BMR x 1.2.
- If you are lightly active (light exercise or sports 1-3 days a week): BMR x 1.37
- If you are moderately active (moderate exercise or sports 3-5 days a week): BMR x 1.5
- If you are very active (hard exercise or sports 6-7 days a week): BMR x 1.72
- If you are extra active (very hard exercise or sports, and physical job or training twice a day): BMR x 1.9
The result will be the number of calories needed to maintain your current weight.
Is calorie counting a good way to lose weight?
Ultimately, to lose weight your calories in must be fewer than calories used. How people achieve this varies. It is a good idea to have an idea of the calories you are consuming in order to be able to balance this equation. You wouldn’t just buy something without knowing the price, and I think calories are a bit like this – it is good to know the basic calorie content of a food or drink.
People often vastly overestimate the number of calories they burn doing exercise too, and then they end up in a calorie surplus and wonder why they are not losing weight. Evidence shows that self-monitoring using food diaries and similar tools to calculate calorie intake does help people lose weight and maintain that weight loss.
The calories we drink should also be considered as people often forget these and they can add a significant number of calories throughout the day. For example, a latte in the morning, juice with lunch and wine in the evening can easily contribute 500 calories to your daily total.
Should you break down your calories by macronutrients? Is it better to get calories from protein rather than carbohydrates, for example?
In terms of weight loss a calorie is a calorie regardless of its source. Whether you’re eating carbohydrates, fats or proteins, all of them contain calories. However, for health where you get calories from is important. It is not healthy to get all your calories from one source such as protein or carbohydrates. It is important to get a balance from all sources.
According to Public Health England’s Eatwell guide (PDF) you should aim to get a third of your calories from complex carbohydrates, a third from fruit and vegetables, a third from protein and dairy sources, with fats and sugars at a minimum. Bear in mind that 1g of carbohydrate and protein provides approximately four calories, 1g of fat approximately nine calories, and 1g of alcohol approximately seven calories.
What is the best way to count calories? How precise do you need to be?
The best way to record calories is to use the technology we have available. Previously we used to keep paper diaries and look everything up in books, but today we are lucky enough to know the calories of foods at the touch of a button. However, bear in mind this will only be accurate if portion sizes are accurate. People often significantly underestimate their portion sizes and thus think they are consuming far fewer calories than they really are. They often put “one portion”, which is 100g, when this is usually far less than the amount they have actually consumed. I think these are the best apps:
Is it worth people considering reducing their calorie intake during lockdown, assuming a lack of activity means they won’t burn so many calories?
This depends on what the person’s goal is. Do they want to lose weight, stay the same or gain weight? And what were they consuming before lockdown? Some people may have increased their activity during lockdown exercising with their kids, or having more time to exercise because they’re not working as much. Some people may have cut down their calories by not eating out, getting takeaways, going to the pub or eating fast food. So I don’t think we can say that everyone needs to decrease their calories during lockdown.