Much has been written on optimizing fat oxidation efficiency through exercise, fasting and low-carb high fat diets, and it’s true these are the big foundations.

But there’s more.

Research efforts on specific foods, are showing encouraging results in their potential to ‘rev-up’ this metabolic chain.

The good news is you’re probably already having these foods.

The question is – are you taking them right?

First a note on Fat Oxidation.

At SFuels we subscribe to four high-level steps in a metabolic chain, that ultimately feed the muscle cell furnace (the mitochondria) with fatty acids, to burn for energy. Here’s the summary –

  1. Lipolysis – the breakdown of Adipose (fat cells) tissue (and also intramuscular fat). Adipose tissue fats are stored as Triacylglycerol which is made up of glycerol and fatty acids. Exercise triggers the hormone epinephrine, which in the absence of heightened insulin levels, triggers the liberation of these fatty acids into the circulation.
  2. Fatty Acid Transport and Uptake into the Muscle Cell – Fatty acids bind to a protein in the circulation called albumin. Endurance training improves circulation to adipose tissue, increasing overall fatty-acid transport to muscle cells. Fatty Acids move from circulation into the muscle cell via a transporter called CD36. CD36 increases in a correlated way to endurance exercise and in fact, remains heightened for several days post exercise.
  3. Transfer into the Muscle Cell Mitochondria – The longer the size of the Fatty Acids (Triglycerides), the slower the process of getting the fatty acids into the muscle cell furnace (the mitochondria) for oxidation. Medium-Chain Triglycerides (MCT) are rapidly transported into the mitochondria – since they do not require transport proteins to enable this. However, Long-Chain Triglycerides (LCT) from adipose tissue and diet do require protein transporters to move into the mitochondria, which takes a little longer. Studies show that exercise intensity between 60-75% VO2Max can regulate (increase) these mitochondria-transporters of long-chain triglycerides.
  4. Oxidation of Fatty-Acids: This is the breakdown of the Fatty Acids in the mitochondria. Both aerobic exercise and high-fat diets can increase enzymes responsible for oxdizing fatty acids. Adrenal hormones drive this process also, while insulin inhibits the oxidation process. The breakdown of fatty acids, then feeds another cycle (Kreb cycle) within the mitochondria, to ultimately release energy (ATP) for the cell.

It’s worth also noting, that fat oxidation isn’t a binary thing, it is not on or off. Fat and carbohydrate oxidation levels move up and down on a gradient in response to our internal metabolism, and external factors like diet, exercise, stress, and the environment around us. Here’s some lab data, showing the shifting % of calories oxidized from Fat and Carbohydrate, relative to exercise intensity (mph, running in this case).

Beyond Exercise, Low-Carb Diets and Fasting.

As noted at the start, the foundation pillars for training efficient fat oxidation include,

Exercise (Aerobic, Endurance and HIIT). Effects all Steps 1 to 4.

Diet approach which minimizes insulin spikes and sustained levels. Effects Steps 1 and 4.

Diet approach which stimulates fat-oxidation enzymes more efficiently burn fat. Effects Steps 4.

These are the foundations, and we cover how Endurance athletes can implement these diet practices in our SFuels QuickStart Guide – CLICK HERE. For those looking for guided education on tuning their endurance training to maximize their fat oxidation, they should enroll in Endure.IQ LDT101 course – CLICK HERE.

However, research is increasingly highlighting specific foods that further stimulate and drive some of these fat-oxidation steps.

The list is long, and growing. For now we’ll focus on two foods, and specifically how to maximize there fat-oxidation potential.

Coffee: It’s Beyond Caffeine.

That amazing aroma, sound and taste of coffee being filtered not only starts our day on the right foot, but can trigger a number of fat-oxidation processes.

While most renowned for its caffeine content, that’s not the only compound that gives Coffee its kick. Depending on the type used and how Coffee is made, active compounds in coffee can vary dramatically. Caffeine can range from 50mg to over 350mg per 100mls. Coffee and its compounds (Cholinergic acids, Caffeine, Trigonelline, Kahweol, Cafestol etc.) trigger many effects in the body, but notably from a fat oxidation perspective coffee can reduce lipogenesis (new or increased size of fat cells), increase Lipolysis (Step 1 above), and increase fatty acid oxidation in the mitochondria (Step 4 above). Different compounds within coffee are triggering these various effects. Caffeine for instance seems to be triggering a lipolytic effect, while the cholinergic acids in coffee would seem more responsible for increased fat oxidation (particularly during sleep) in the mitochondria (furnace of the cell). Both human and animal studies have been published for several decades on the glycogen sparing effect of caffeine, via release and oxidation of fatty acids.

Now this all sounds good but there is a few checks and balances for coffee to deliver its positive effects on fat-oxidation –

  1. As noted earlier for lipolysis to be activated – insulin cannot be present in heightened levels. So if we’re taking coffee with sugar, or a carbohydrate-based snack with coffee, the lipolytic effect will likely be blunted, or notably diluted. Similarly, for fatty acid oxidation in the mitochondria to be activated, this also needs to happen in a low insulin state.
  2. Its more beneficial to take coffee without milk/dairy, as its probable that the cholinergic acids (similar to other phyto-nutrients) could end up bound to the protein in milk – thereby losing the effect of the cholinergic acids.
  3. While we’re on caffeine in coffee, here’s couple of articles, on how you might respond to caffeine during an endurance race, and it’s association with mild-laxative effects, and, gut-cramping and gas effects, in the cycle-run leg of triathlons.
  4. Meta-studies on coffee are showing promise of coffee consumption with respect to obesity, and insulin resistance, however in balance, it should be noted that coffee has also been found as a factor in heightened blood pressure.
Recommendations for Optimizing Fat-Ox with Coffee
  1. Take your Coffee, black, without sugar, without artificial sweeteners and without milk.

2. Take your coffee away from carbohydrates as best/much as possible. If you want to eat something with your coffee, include a low-carb snack like, cheese, nuts, avocado, SFuels LIFE Bar, or a Keto snack recipe.

3. If you’re looking for an iced coffee, or shake while avoiding the milk interference with coffee’s fat-oxidation potential, add whole cream (which has very low protein and lactose) and SFuels LIFE, for a creamy and sweet Latte like experience.

Cacao-Chocolate. Beyond its name.

Theobroma Cacao – or in modern day English, ‘Food of the Gods’. Cacao lives up to its name, whether measured by taste, or the highly active compounds within.

Cacao powder, or nibs from the cacao bean is an extremely complex food, with over 300 compounds in its makeup. Cacao, is different to its similar – but high heat-treated brother ‘Cocoa’. While containing caffeine, the levels in Cacao are dramatically lower than coffee, and it is not caffeine that is the most interesting in its health giving effects.

As its botanical name ‘Theobroma Cacao’ hints, Cacao is high in the compound Theobromine. While less stimulating than caffeine, Theobromine also works its effects through the central nervous system.

As it relates to Cacao revving up fat oxidation, its not the caffeine, or the Theobromine – so what is it?

Cacao, contains high and rich levels of polyphenols, more widely referred to as anti-oxidants. Aside from the color and taste these polyphenols give to Cacao, they’re also at the center of the health giving effects. Particularly a sub-set group of these polyphenols called flavonoids, and notably one compound called ‘flavan-3-ols’,This is the compound that is showing promise behind Cacaos effect on fat oxidation. Now there’s a big catch with polyphenols, they are heat-sensitive. It is heat (over 260F) that transforms Cacao into Cocoa. This heat processing has a significant and measurable degrading effect on the flavonoids. Your best bet is to choose and consume, raw cacao (powder, nibs or butter, or chocolate) which have not been roasted or heated, and as a result have kept the maximum amount of the flavonoids intact.

Specific fat oxidation studies have shown flavan-3-ols enhance both Lipolysis, and also trigger the biogenesis (creation) of incremental mitochondria – which as you know from step 4 above is where fatty acid oxidation occurs. Notably the flavonoid is found to be specifically active in aiding the process of long-chain fatty acid oxidation. In 2018, a meta-study review was conducted on over 200 random controlled trials on flavan-3-ols and their role in clinical outcomes to cardiovascular disease and diabetes.

Recommendations for Optimizing Fat-Ox from Cacao-Chocolate
  1. If you’re a chocolate lover, choose a Cacao (not Cocoa) based chocolate. Again, you want to limit the sugar-carbohydrate to turn on lipolysis, so choose a Chocolate with 70% or higher cacao.

2. Cold-extrude or cold-form your Cacao-chocolate based cookies and bars (SFuels LIFE bar). Avoid baking them, so as not to degrade the Cacao flavonoids.

3. If you’re going use Cacao as a hot chocolate drink – then keep the temperature ‘warm’ , below 110F. Use whole cream and SFuels LIFE for creamy sweet experience, and avoid the use of milk.

What else –

As mentioned earlier, there is a long list of foods which can stimulate fat oxidation – various teas, fermented vegetables like Kimchi, and other polyphenols like resveratrol in peanuts, pistachios, grapes, red wine and more. Likely, we need a part 2 on this topic – but I’m sure you’ll enjoy getting started with Coffee and Cacao-Chocolate.

Be Well, Go Longer. Team SFuels.


  • Mechanisms of action of coffee bioactive components on lipid metabolism. Renalison Farias-Pereira, Cheon-Seok Park, Yeonhwa Park. Food Sci Biotechnol. 2019 Oct; 28(5): 1287–1296.
  • Coffee, Caffeine, and Health Outcomes: An Umbrella Review. Giuseppe Grosso, Justyna Godos, Fabio Galvano, Edward L Giovannucci. Annu Rev Nutr . 2017 Aug 21;37:131-156.
  • Caffeine as a lipolytic food component increases endurance performance in rats and athletes. S Ryu , S K Choi, S S Joung, H Suh, Y S Cha, S Lee, K Lim. J Nutr Sci Vitaminol (Tokyo). 2001 Apr;47(2):139-46
  • Flavan-3-ol fraction from cocoa powder promotes mitochondrial biogenesis in skeletal muscle in mice. Naoki Watanabe, Kodai Inagawa, Masahiro Shibata, and Naomi Osakabe. Lipids Health Dis. 2014; 13: 64.