A food habit you repeat every day changes your weight more than a diet you keep for a month. One heaped teaspoon of sugar in your coffee is 27 calories. Drop it for good and your weight goes down by about 1.2 pounds (0.6 kg) in the first year and 2.5 pounds (1.1 kg) within three years, with no diet and nothing to count. Swap the oil, the mayo and the second slice of bread as well, and it's about 11 pounds in the first year and over 20 within three years, with the same meals on your plate. These figures are for an average adult with weight to lose.
Why a small habit beats a diet
A diet ends. A habit runs every day, 365 times a year, and once it's set it takes no decision and no effort. That's how a 27-calorie spoon of sugar adds up to 9,855 calories a year.
Kevin Hall's team at the NIH built a model of how body weight responds to one lasting change in eating and published it in The Lancet in 2011. Their rule of thumb: every 10 calories a day you cut for good lowers your weight by about one pound. Half of that comes off in the first year, and almost all of it within three years. As long as the new habit stays, the weight stays off.
One example: a spoon of sugar
USDA FoodData Central lists granulated sugar at 387 calories per 100 grams. A level teaspoon, scraped flat, holds 4.2 grams, but nobody sweetens coffee like that. With the small heap you get when you scoop from the bag, a teaspoon holds about 7 grams. That's 27 calories per teaspoon, and nothing that keeps you full.
| Heaped teaspoons a day | Calories a day | Calories a year | Off in year one | Off within 3 years |
|---|---|---|---|---|
| 1 | 27 | 9,855 | about 1.2 lb (0.6 kg) | about 2.5 lb (1.1 kg) |
| 2 | 54 | 19,710 | about 2.5 lb (1.1 kg) | about 5 lb (2.3 kg) |
| 4 | 108 | 39,420 | about 5 lb (2.3 kg) | about 10 lb (4.5 kg) |
| 6 | 162 | 59,130 | about 7.5 lb (3.4 kg) | about 14.9 lb (6.8 kg) |
| One 12 oz can of cola | 140 | 51,100 | about 6.5 lb (2.9 kg) | about 12.9 lb (5.9 kg) |
Sugar: USDA FoodData Central, 7 g per heaped teaspoon. Cola: 39 g sugar, 140 calories per 12 oz can (label). Weight: the Hall model (NIH, The Lancet, 2011), for an average adult with weight to lose. A heavier person loses a little more, a lighter one a little less.
Two heaped teaspoons is a sweetened coffee and a sweetened tea. Most people eat far more: the American Heart Association puts the average American adult at about 70 grams of added sugar a day, roughly 10 heaped spoons, most of it in drinks and packaged food rather than from a spoon.
Other habits that work the same way
Sugar is one example. Mayonnaise, oil in the pan, butter on toast, the second slice of bread and the evening beer follow the same math, and most of them carry more calories than a spoon of sugar. Each one has a swap that keeps the dish.
| Habit (calories) | Swap (calories) | Calories saved a day | Off in year one | Off within 3 years |
|---|---|---|---|---|
| 2 heaped teaspoons of sugar in your coffee (54) | No sugar | 54 | about 2.5 lb (1.1 kg) | about 5 lb (2.3 kg) |
| 1 tbsp mayonnaise in a sandwich or salad (94) | 1 tbsp nonfat Greek yogurt (9) | 85 | about 3.9 lb (1.8 kg) | about 7.8 lb (3.6 kg) |
| 2 tbsp sour cream on a potato or tacos (48) | 2 tbsp nonfat Greek yogurt (18) | 30 | about 1.4 lb (0.6 kg) | about 2.8 lb (1.3 kg) |
| 1 tbsp oil in the pan (124) | 1 tsp oil (40) | 84 | about 3.9 lb (1.8 kg) | about 7.7 lb (3.5 kg) |
| 1 tbsp butter on toast (102) | 1 tsp butter (34) | 68 | about 3.1 lb (1.4 kg) | about 6.3 lb (2.8 kg) |
| A second slice of bread (77) | One slice | 77 | about 3.6 lb (1.6 kg) | about 7.1 lb (3.2 kg) |
| 8 oz glass of orange juice (112) | A whole orange (62) | 50 | about 2.3 lb (1 kg) | about 4.6 lb (2.1 kg) |
| 12 oz can of regular beer (153) | No beer | 153 | about 7.1 lb (3.2 kg) | about 14.1 lb (6.4 kg) |
| 2 tbsp ranch on a salad (130) | 1 tbsp ranch (65) | 65 | about 3 lb (1.4 kg) | about 6 lb (2.7 kg) |
Calories: USDA FoodData Central, my tablespoon table for the spoon-sized foods. Weight: the same Hall model, for an average adult with weight to lose.
Three swaps together, a teaspoon of oil instead of a tablespoon, Greek yogurt instead of mayo and one slice of bread instead of two, come to 246 calories a day. That's about 11 pounds (5 kg) in the first year and over 20 pounds (10 kg) within three years, with the same meals on your plate. Beer is the biggest single line in the table, and the math behind drinks has the rest of it.
None of these swaps takes a dish off your plate. The salad is still a salad and the sandwich is still a sandwich, which is why they're easy to keep for years.
How to find your own habits
Your habits are the things you eat on an ordinary day without deciding: the sugar in your coffee, the oil you pour in the pan, the sauce on your sandwich, the drink with dinner, the snack in the evening. Tomorrow, write down everything you eat and drink in one ordinary day, spoonfuls included. Don't change anything yet, just write it down.
Then look up the calories. My tablespoon calorie table covers oils, sauces, spreads and sweeteners. For anything with a label, here's how to read a nutrition label; 7 grams of added sugar is one heaped teaspoon. The coffee calorie breakdown shows how much a pump of syrup adds to a latte.
What I learned from the weight coming back
I went from 271 pounds to 183, then back up to 249, then down to 170 where I am now. The 66 pounds didn't come back after one big meal or one bad week. Evening snacks and sugar came back first: a hot sandwich in the evening, then two, then sugar on top. Each one was small enough that I didn't count it.
That's the table above, running in the wrong direction. Sixteen calories here and a few hundred there, kept every day for months.
The second time I lost the weight, I learned the math first: calorie deficit, protein, how much a portion really is. Then I built an ordinary day that needs no decisions: two meals, each one 250 grams of meat, 100 grams of raw rice or pasta and vegetables, with different food in those slots every day. The full method, with my day and a swap table, is in how to lose weight without counting calories every day.
How to change a habit without missing it
Change one habit at a time and shrink it before you drop it. Half a teaspoon less sugar for a week, then none. A teaspoon of oil in the pan instead of a tablespoon. One slice of bread instead of two.
Expect your taste to change, but not what you like. In a 2016 study in the American Journal of Clinical Nutrition, people who ate less sugar for three months rated the same pudding about 40% sweeter than people who didn't. Their favorite level of sweetness didn't move, though, and when the study ended most of them went straight back to their old intake.
So change what you buy and order, and leave your taste out of it. Put Greek yogurt in the fridge where the mayo used to be. Buy unsweetened yogurt and plain oats. Stop keeping cola and beer in the fridge. Order the coffee without the syrup.
To find your own starting number, the daily calorie intake calculator gives you the number to work from, and the weight loss calculator shows how long a bigger change takes.
What to do this week
Write down what you eat tomorrow. The day after, pick the habit you'd miss least, whether it's the sugar in your second coffee, the tablespoon of oil or the second slice of bread, and change it. Leave everything else alone for a week, then pick the next one.
If you'd rather see what a full day of eating looks like at your number, the free meal plan generator builds one in a few seconds.
