Consistent exercise changes how saturated fat is used by the body

An active lifestyle can change how the body burns saturated and unsaturated fat according to new research from the University of Aberdeen.

In the study, funded by the British Heart Foundation and published in Nature Communications, researchers investigated how different types of fat are used by the body, depending on the individual’s level of physical fitness.

While this study did not look at diet, which is notoriously difficult to control, it examined how fat is metabolised. The researchers analysed the effects in two groups – ‘super healthy’ male athletes and males with type 2 diabetes who did little to no exercise.

Both groups swapped exercise regimes for 8 weeks.

The athletes underwent ‘deconditioning’ where they went from exercising vigorously for at least 9 and a half hours per week to none. In contrast, the people with type 2 diabetes underwent endurance training where they exercised for 5 hours a week.

Before and after the lifestyle swap, the volunteers received small amounts of different fats via an intravenous injection and had MRI scans to see how the fat behaved inside their muscle cells.

Results showed the group with type 2 diabetes lost weight, improved their insulin sensitivity and lowered their cholesterol, triglycerides and fasting glucose levels.

The team, led by Professor Dana Dawson, also found that in athletes, saturated fat is used intensely for physical activity as the ‘preferred source of energy.’

“We discovered that athletes store and utilise saturated fat intensely for high performance physical activity and conversely in people with type 2 diabetes, we observed predominantly storage” said Professor Dawson, Chair in Cardiovascular Medicine at the University.

“We also showed in people with type 2 diabetes that endurance exercise training increased the storage and utilisation of saturated fat in their skeletal muscle cells to the extent that they became similar to the deconditioned athletes after 8 weeks of training.

“Overall, the most striking and completely new perspective we have taken from this study is that one size ‘doesn’t fit all’ and that one’s cardio-metabolic health dictates how efficiently you’re able to use different fats as fuel.

“These results are completely novel and highlight how keeping fit and active improves metabolism of saturated fat as a direct benefit of exercise.”

Fergus McKiddie, 56, from Aberdeenshire took part in the trial in the athlete category. Fergus who works for NHS Grampian is in peak fitness and leads an active lifestyle which includes running, cycling and weight training, which made him a perfect candidate for the swap. Fergus said: “My mother-in-law had type 2 diabetes for many years before developing vascular dementia.

“So – I felt like I should try to help in any way I could to try to advance the understanding and treatment of the disease.

“It was a bit of a shock to the system to go from exercising every day to doing nothing and it took a bit of getting used to. But I am glad that I contributed towards this exciting result.

“It has changed my outlook on how I eat now – I’m now less concerned about eating natural fats as I understand better how my body is handling them and making good use of them.

“It also really highlighted the importance of exercise for everyone especially those with type 2 diabetes so I would like more people to know that.

“It was a very interesting experience and produced an exciting result that potentially opens up new ways to assist with the ever-increasing numbers of patients being diagnosed with type 2 diabetes. An illness that has touched me and my family deeply.”

Ian Frizell, who has type 2 diabetes and took part in the swap added: “I enjoyed the experience and the outcome – certainly the health benefits.

“Following the swap, I experienced weight loss, increased fitness level, lowered blood sugar level and an improvement in cholesterol readings.

“The routine of measured exercise every day was the key to the success of the programme.”

Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, supported the research, saying: “This small study reinforces the benefits of keeping active on our heart health. While the study compared two very specific groups – male athletes and men with type 2 diabetes – the findings offer reassurance that being physically active can improve how the body uses different types of fat.

“Importantly, the study did not assess the impact of consuming fat, and the existing advice remains to try and replace saturated fat in the diet with unsaturated fat.

“Daily physical activity can reduce the risk of cardiovascular disease by lowering cholesterol, triglycerides and fasting blood sugar levels, as well as helping to maintain a healthy weight. When it comes to being active, it’s important to get into a routine that you enjoy and that you can stick to. Try to build up to 150 minutes of moderate intensity activity a week, such as a brisk walk, swimming or cycling.”