Ever wondered whether you can really hack your metabolism? Do fat burning supplements, fasting and HIIT training really help your body burn more fat?
Here’s what works (and what doesn’t) when it comes to burning more body fat.
DO FAT BURNING FOODS REALLY EXIST?
Some foods do have the ability to increase our body’s metabolic rate. The ‘thermic effect of food’ is a temporary increase in the body’s metabolic rate that occurs after eating certain foods. Protein rich foods, for example, have a greater thermic effect compared to those that are predominantly carbohydrate or fat.
Other foods can speed up our metabolic rate (the rate at which we burn calories) too, however, the effects are often very modest. Take capsacin, a compound found in hot chilli peppers, which has been shown to increase the amount of calories our bodies burn. An analysis of 20 scientific studies found that while capsaicin can stimulate the metabolism, the result were modest. The average increase of 50 calories burnt per day isn’t huge and is unlikely to have a noticeable effect on fat loss.
WHAT FOODS SHOULD YOU AVOID IF YOU WANT TO BURN FAT?
The main foods to avoid are those that are highly processed and high in sugars and starchy carbohydrates (which break down into simple sugars in the digestion process). These foods provide easy energy for the body so it will prioritise burning these for fuel over burning stored body fat.
We are all aware of high-sugar processed foods such as biscuits, cakes and sweets. Watch out for those healthy-looking granolas, energy bars and balls too, many of which can contain a surprising amount of sugar too.
As for starchy carbohydrates, we’re talking about things like bread, pasta and other white flour based products, rice and cereals. Even the whole grain versions. While whole grains are more nutrient dense and will be broken down more slowly, they’re still providing carbohydrates. The body will prioritise burning any carbohydrates as fuel before it turns to burning stored body fat.
This explains why low carbohydrate diets can be so effective for fat loss. That’s not to say that you have to cut out carbohydrates completely to lose weight, but watching your sugar intake is always a good idea from both a health and weight loss perspective.
DOES EATING FAT HELP YOU BURN MORE FAT? IS THE KETO DIET WORTH TRYING?
It’s not quite as simple as ‘fat burns fat’. Significantly increasing your fat intake without addressing any other areas of your diet is more likely to result in weight gain than weight loss. A ketogenic diet does involve getting a greater percentage of your calories from fat and can be a very effective way to reduce body fat. However, in addition to increasing your healthy fat intake, it’s also essential to keep your carbohydrate intake very low in order to enter the fat-burning state of ketosis. It’s important to take into consideration your fat, protein and carbohydrate intake when embarking on a weight loss plan.
DOES FASTING HELP OR HINDER YOUR METABOLISM?
When done in the right way, fasting can focus your body on burning more fat. When you haven’t eaten for an extended period of time your body will likely have used up most of the sugar in your blood stream provided by your last meal. It will then turn to using the stored glycogen in your liver and muscles cells for energy. Once these stores start to deplete, your body will increasingly turn to body fat for fuel.
If we are optimising our diet to help us burn body fat, our body will likely be burning a combination of carbohydrates and fat most of the time. However, restricting your eating window can help to tip the balance in favour of burning more fat. It is important to ensure that you consume a nutrient dense diet when you do eat, providing optimal amounts of protein to prevent muscle loss which will compromise your metabolic rate.
Different fasting approaches and eating windows suit different people. Work on finding the approach that works best for you. One way to identify your ideal eating window is to use a device like Lumen which can measure your metabolism and tell you the extent to which you are burning carbohydrates or fat. As well as giving advice on what to eat, it helps you identify the ideal times to eat in order to promote fat loss for you specifically.
SHOULD YOU EXERCISE ON AN EMPTY STOMACH TO BURN MORE FAT?
When you haven’t eaten for an extended period of time, your body is more likely to turn to stored body fat to fuel your workout. Hence why fasted training can help with fat loss.
However, the answer to whether fasted exercise is better for fat loss is not quite so straightforward. To effectively hack your metabolism we need to consider the body as a whole.
Exercising on an empty stomach first thing in the morning, when cortisol levels are already at their peak, can cause a further spike. For anyone who is affected by increased stress levels, further triggering the release of cortisol is not advisable. This is going to have overall negative impacts on fat loss, health and anxiety.
WHAT KIND OF EXERCISE IS BEST FOR BURNING FAT? IS HIIT ALL IT’S CRACKED UP TO BE?
While HIIT training is known to increase fat burning in the short term and certainly for some it does effectively promote fat loss, but it’s not necessarily the best approach for everyone.
I have worked with clients who have been exercising intensively – going to HIIT classes daily while committing to a low calorie diet and they have come to me when, despite a consistent calorie deficit, they are still not losing weight. In situations like this, the combination of intense exercise coupled with a low calorie diet is causing the body so much stress it refuses to let go of fat. When I work with clients like this I reduce their exercise and increase their calories (from healthy foods, of course) and low and behold, the weight starts to come off. As counterintuitive as that may seem.
Again, it’s about finding what’s right for you. HIIT might work for some, but for others this style of training might aggravate injuries or areas of weakness. Also, if you are forcing yourself to do a style of exercise you really don’t enjoy, you’re unlikely to commit to it in the long run. I encourage my clients to find an exercise they enjoy doing, something that makes them feel good and that they are happy to commit to. Consistency is key. It’s much better to do a less intense form of exercise that you’re happy to commit to long term, rather than pushing yourself to do something you hate and is unlikely to last more than a couple of weeks.
IF YOU WANT TO LOSE WEIGHT, HOW CAN YOU ENSURE YOU BURN FAT AND NOT MUSCLE?
One of the most important considerations is ensuring your diet has enough protein in it. Muscle is made from protein so it’s crucial we get enough in our diet to prevent muscle loss. It’s one of the most common mistakes I see people make – they drop their calorie intake in an attempt to lose weight – but they don’t pay close enough attention to where those calories are coming from and subsequently, protein intake is reduced and muscle mass lost. This might mean that the number on your bathroom scale drops more quickly, but it’s really not helpful for fat loss in the long term at all. Or our health for that matter. Active women should aim for 1.2g upwards protein per kg body weight per day, though the ideal amount for you can vary depending on a number of different factors.
CAN SUPPLEMENTS BOOST YOUR METABOLISM?
There are a small handful of supplements that have been shown in research to promote fat loss. However, don’t expect miracles! In most studies, fat loss as a result of taking these supplements has been modest. Here are three you can try, should you wish:
ProVen Probiotics ShapeLine. A probiotic supplement for weight loss developed by Professor Nigel Plummer. A nine-month study of 70 overweight participants who took ShapeLine resulted in losses of 3.2kg (7lbs).
Conjugated Linoleic Acid (CLA). I wrote my dissertation on the different mechanisms by which CLA can support fat loss. It can result in moderate fat loss benfits and has also been shown to help prevent weight gain over periods of excess (eg Christmas / holidays).
Theromogenics. Supplements like green tea, green coffee bean extract and capsaicin. Try Solgar’s Thermogenic Complex.
WHAT ARE THE GOLDEN RULES FOR FAT LOSS?
Identify the right dietary approach for you and ensure it’s nutritionally sound. There are a lot of diets out there and finding the right one can be a minefield. It’s important to ensue that a diet plan will not only promote fat loss, but also that it’s nutritionally complete and is sustainable from a practical perspective.
Structure your meals around a source of protein, healthy fats and plenty of veg / salad. Keep highly processed foods, sugar and starchy carbohydrates to a minimum.
Drink enough water and get enough sleep.
Train consistently in a way that suits your body.
Plan ahead. Find healthy meals that you enjoy eating and focus on what you can have.
Know that there is no one size fits all approach. Keep a journal and track not only what you eat, but also how you’re feeling alongside your weight and measurements. Reflect on what’s going well and where your challenges lie. This will enable you to learn along the way what works for you.
Finally, consider getting professional help. It’s easy to think that your should be able to do it by yourself (especially given all of the nutrition and fitness information you’ve likely consumed). But successful long term weight loss is rarely as straight forward as ‘less calories, more exercise’. My Intelligent Weight Loss Method ensures you’re comprehensively supported in reaching your goal weight and maintaining it for good. If you’d like to explore how we can help you, please book in for a complimentary call to find out more.