We've all heard it: drinking green tea and eating chilli is fat burning.
It's music to the ears of every person trying to get in shape. Hours of exercise? No need, we can just have these foods by the bulk.
Although we all really, really wish it were true, unfortunately, it's not as simple as drinking endless cups of green tea and losing 10 kilos.
"There’s not a lot of evidence to say we should be smashing down chillies or green tea in terms of their metabolism boosting or fat burning properties. It’s very, very negligible," Lauren McGuckin, accredited practising dietitian and spokesperson for the Dietitians Association of Australia, told The Huffington Post Australia.
The hyped up, supposed 'fat burning' foods and drinks in question include chilli, black pepper, green tea, coffee, coconut oil and grapefruit -- however they have not been found to significantly cause a measurable increase in metabolism.
"You wouldn't place all your eggs in any of those baskets by eating or drinking tons of those things to accelerate weight loss. It's definitely not proven," McGuckin said.
"We don’t want people to rely on those foods in order to burn fat or lose weight, otherwise they are going to miss out on everything else our body needs."
However, not all hope is lost: although not 'fat burning', our bodies do actually burn more calories when digesting certain food groups, due to their diet-induced thermogenic effect.
"Above and beyond our resting metabolic rate, which is our basic energy needs just to survive (without factoring in exercise), there is an additional 10 percent of energy burned that is basically due to chewing, digesting and processing the food we eat," McGuckin said.
"Thermogenic foods may help to increase a person's metabolism by enhancing thermogenesis, the process when the body burns calories to utilise the foods you have just eaten, converting those calories into heat," celebrity trainer and former NRL player Ben Lucas told HuffPost Australia.
"This is probably why things like capsaicin in chilli is believed to boost metabolism. In a sense it’s warming things up a bit so it does increase that diet-induced thermogenesis, but we don't know how much of that has actually increased our metabolism," McGuckin said.
The food groups that are more likely to activate this diet-induced thermogenesis are whole grain carbohydrates, protein and fats.
"Protein tends to take more of that 10 percent than carbohydrates and fats do, but in terms of there being a notable or significant contribution from any particular food to increase in metabolism, there’s not a lot of evidence to prove this," McGuckin said.
Instead of focusing on specific 'fat burning' foods, McGuckin recommends focusing on the broader range of healthy food groups: whole grains, healthy fats, lean protein and lots of veggies.
"In terms of getting your metabolism going, or weight loss in general, essentially we want people to fill up on foods that are low in energy so they’re not overeating the unhealthy, energy-dense foods," McGuckin told HuffPost Australia.
"Things like dietary fibre, which we get from fruit and vegetables (veggies being the lowest calorie source of fibre), whole grain breads and cereals and legumes all help to keep us full. Make sure there’s a lean source of protein to help with this, too.
"This should be the focus. This is what you’re more likely to see benefits from, rather than picking chilli or green tea."
While eating and drinking these popular 'fat burning' foods is not going to harm your weight loss, they shouldn't be the first or only strategy. Concentrate instead on eating a variety of healthy whole foods and exercising regularly.
"Diet is so much more complex than these little things we like to hone in on that are in the media," McGuckin said.
"I think you can use them in conjunction with a healthy eating plan and an exercise program. Every little bit helps, but I certainly wouldn’t rely on these foods alone," Lucas said.