Losing weight demands some serious life changes. After all, you need to burn 3,500 more calories than you take in to lose just 0.5kg. But if you cut 500 calories a day, you can lose half a kilo per week — and it will be fairly painless.

"Calorie bargaining is all about making swaps and developing habits that are sustainable for the long-term rather than just depriving yourself," says Charles Platkin, distinguished lecturer at Hunter College and City University of New York School of Public Health. "A simple swap that cuts 500 calories has a multiplier effect: If it's something you eat three or four times a week, you cut at least 1,500 calories."

To help guide you, we've put together 20 simple calorie-cutting tips to get you to your weight loss goal.

1. Have your sandwich on a salad.
Two big slices of bread with mayo can tally up to 550 calories. 

2. Skip the happy hour margarita.
If your margarita comes in a large glass you are tacking on around 800 calories - more than a meal's worth.

3. Opt for black.
A grande latte with no added sugar has 220 calories, while a cup of black coffee has 2. If you typically drink two cups with some sweetener, you're saving at least 500 calories when you switch to black, says Platkin.

4. While you're at it, try a cold brew iced coffee.
You'll save about 405 calories over a Starbucks Grande Mocha Frappuccino. 

5. Chew slower.
Chewing each bite twice as much as you normally do allows you to feel fuller on less food. Research suggests you can reduce what you eat at each meal by 100 to 120 calories -eliminating nearly 400 calories - and you can be satisfied on smaller snacks this way, as well.

6. Quench your thirst with water and a lemon squeeze instead of soda.
You'll save nearly 200 calories for every cola you skip; swap out three drinks a day and you'll easily clear 500 calories.

 7. Cook your meals at home.

A 2014 study found that people who cooked dinner at home consumed about 140 fewer calories than people who typically ordered in, dined out, or heated up pre-made meals. Make your own breakfast and lunch and you'll be nearing that 500-calorie deficit.