Systematic Solutions

27/11/2017

Weight loss is great for your health - even if it's just a little. This is the conclusion from a recent systematic review and meta-analysis from Aberdeen, Scotland.

The authors looked at 54 randomised controlled trials (RCTs) involving 30,206 people. Most trials analysed the effects of low-fat diets aiming to reduce obesity (weight-loss diets).

Losing weight resulted in a reduction in all-cause mortality (dying for any reason) of 18%, even though most trials were of a relatively short duration (around 2 years).

Impressively, the average weight loss in the studies was only 3.4 kg, meaning that this substantial risk reduction was associated with a reduction in weight of only about 5%.

So if you ever feel disheartened about your weight loss, just remember that every bit helps.

You can see the whole study here:
http://www.bmj.com/content/359/bmj.j4849

06/11/2017

Can low-energy sweeteners (LES) help you lose weight? Or do you end up eating more? This was the question asked by researchers from Europe. They looked at the evidence for energy intake and body weight from both human and animal studies.

They found that in animal studies, consumption of low-energy sweeteners reduced body weight in 22 of 47 studies (47%). There was no difference in body weight in 21 studies, and an increase in body weight in 4 studies. At high doses, body weight was decreased in 18 studies (53%), with 13 showing no difference and three showing an increase.

HOWEVER, when the animals are allowed to eat as much as they want, in some studies there is no difference in food intake, whereas in other studies the addition of LES to food leads to an increase in food intake and body weight.

The authors also looked at observational studies (cohort studies). In these studies, groups of people who have different lifestyles or take different medications (or other factors) are compared. Importantly, they are not randomised to different groups, so you can never be sure if the effects you see are due to factors other than your area of interest.

In the cohort studies, there was no difference in body mass index (BMI) between those consuming LES and those who did not consume LES. This was true for both adults and children.

Finally, we have randomised controlled trials (RCTs). These are the gold standard in research - as long as they are well-conducted. The first set of RCTs looked at how much food people consume if given foods and drinks with LES. In these studies, there was very little or no difference in energy intake.

In longer-term studies (1.25 to 40 months), adults consuming LES-sweetened beverages lost 1.4 kg more than those consuming sugar-sweetened beverages. The results were similar for children (1.35 kg). People consuming LES-sweetened beverages lost on average 1.24 kg more than those consuming plain water.

In conclusion: the highest quality evidence suggests that LES-sweetened beverages can aid in weight loss. The increase in weight loss, however, is moderate (1.2 - 1.4 kg).

You can read the study for yourselves here!

International Journal of Obesity is a monthly, multi-disciplinary forum for papers describing basic, clinical and applied studies in biochemistry, genetics and nutrition, together with molecular, metabolic, psychological and epidemiological aspects of obesity and related disorders