Boosting omega-3 fatty acid intake is unlikely to prevent type 2 diabetes
Increasing the intake of polyunsaturated fats in the diet with supplements of omega-3 fatty acids, for example, is unlikely to affect people’s risk of developing type 2 diabetes. However, this review only looked at the effect of supplements on diabetes, not wider health.
This large systematic review included 83 long-term trials comparing higher and lower intake of omega-3 and omega-6 fatty acids and total polyunsaturated fats in healthy adults and those with existing diabetes. It found no...
Diet and physical activity interventions targeting children and youth have different, yet small, effects on preventing obesity
Obesity prevention interventions which include both diet and physical activity may reduce the risk of obesity in pre-school children. Once at school, physical activity appears to be more effective for weight loss than diet alone. Resulting weight loss form any intervention, if any, has been very small with unclear benefits to the individual or population.
This NIHR-supported Cochrane systematic review pooled the results of 153 global randomised-control trials (sevenfrom the UK) aiming to preven...
Mixed evidence shows some impact of mass media campaigns promoting tobacco control, physical activity and sexual health
Mass media campaigns have demonstrated effectiveness for promoting tobacco control, physical activity and sexual health. Most of the evidence relates to improving awareness of health risks or the availability of services. However, for those aimed at the risks associated with sedentary lifestyles, smoking or sexual behaviours, there are signs that the campaigns also achieved positive changes to the target behaviour.
This large review, funded by NIHR, identified 36 systematic reviews and individu...
One gram a day of omega-3 supplements does not reduce the risk of cancer or cardiovascular disease
A trial of omega-3 fatty acid supplements showed they have little or no effect on the risk of cancer or cardiovascular disease in the general population. The finding contradicts the widespread belief that these supplements at usual doses protect the heart.
A large trial of 25,871 men and women in the United States compared the impact of taking about 1g a day of omega-3 fatty acid supplements with placebo on major cardiovascular events and invasive cancer. The results are consistent with a recen...
Treating vitamin D deficiency may reduce exacerbations of COPD
Vitamin D supplements halve the number of exacerbations of chronic obstructive pulmonary disease (COPD) in people with low levels of the vitamin, from two per year to one per year. The supplements do not affect exacerbations of COPD in people who are not deficient.
This NIHR-funded review is the first to pool individual-level data from randomly controlled trials to see whether taking vitamin D can help reduce exacerbations.
People with moderate to severe COPD may be at risk of low vitamin D le...
A high omega-6 fatty acid diet is unlikely to prevent cardiovascular disease or deaths
Diets or supplements that aim to increase omega-6 fatty acids have no clear effect on the risk of cardiovascular events like heart attacks or stroke, overall deaths or deaths from cardiovascular disease. Omega-6 fatty acids are poly-unsaturated oils largely derived from seeds and nuts such as sunflower oil, corn oil, soybean oil, walnuts and pumpkin seeds.
The results of this Cochrane review can be looked at alongside another recent Cochrane review, which found no benefits of fish oil in omega-...
No additional weight-loss reported from a lifestyle programme for people with psychosis
For adults with psychosis, such as schizophrenia, who are taking antipsychotic medication, a carefully designed 12-month group diet and exercise programme did not lead to clinically important weight loss after 12 months. The programme was compared with those receiving usual care including written lifestyle advice. Intervention and usual care groups each lost half a kilo on average, with no measurable changes in diet or physical activity.
People with schizophrenia are twice as likely to be overw...
A total diet replacement programme helped obese people lose weight and keep weight off
A programme of weekly behavioural support with total diet replacement led to over 7kg greater weight loss than usual care in primary care. This weight loss was maintained for a year after starting the 8-12 week low calorie programme.
This trial, funded by NIHR and a commercial sponsor, was carried out in ten primary care practices in Oxfordshire. Participants had BMI over 30. It referred half of the 278 participants to a commercial weight loss programme, free of charge for six months. The rest ...
Diet and exercise can reduce the risk of developing diabetes during pregnancy
Diet and exercise are effective ways of preventing the development of diabetes during pregnancy, known as gestational diabetes.
Gestational diabetes is becoming more common and is associated with poorer outcomes for mother and baby. Diet, physical activity and weight are modifiable risk factors, but trials published to date have shown inconsistent results.
This systematic review pooled 47 trials and found that any form of lifestyle intervention reduced the risk of gestational diabetes by 23%, ...
Fish oil supplements do not reduce cardiovascular deaths in people with diabetes without existing vascular disease
Omega-3 fatty acid supplements make no difference to cardiovascular outcomes in people with diabetes but without established cardiovascular disease. Serious vascular events like heart attack, stroke or deaths from these occurred in about 10% of people regardless of whether they took daily omega-3 or placebo capsules for seven years.
The ASCEND studyis a large UK trial assessing primary cardiovascular prevention for people with any type of diabetes. A companion publication assesses the use of as...