Field Notes

Intermittent Fasting Could Improve Obese Women’s Health

Research carried out at Australia’s University of Adelaide shows that obese women lost more weight and improved their health by fasting intermittently while following a strictly controlled diet.

The study, recently published in the journal Obesity, involved a sample of 88 women following carefully controlled diets over 10 weeks.

“Continuously restricting their diet is the main way that obese women try to tackle their weight,” says Amy Hutchison, PhD, lead author of the study, from the University of Adelaide and the South Australian Health and Medical Research Institute (SAHMRI).

“Unfortunately, studies have shown that long-term adherence to a restricted diet is very challenging for people to follow, so this study looked at the impact of intermittent fasting on weight loss,” Hutchison says.

“Obese women who followed a diet in which they ate 70% of their required energy intake and fasted intermittently lost the most weight. Other women in the study who either fasted intermittently without reducing their food intake, who reduced their food intake but did not fast, or did not restrict their diet at all, were not as successful in losing weight,” Hutchison continues.

The study also checked the effect of the different diets on the women’s health. Women who fasted intermittently as well as restricting their food improved their health more than those who only restricted their diet or only fasted intermittently.

“By adhering to a strict pattern of intermittent fasting and dieting, obese women have achieved significant weight loss and improvements in their health such as decreased markers for heart disease,” Hutchison says.

Participants who fasted intermittently ate breakfast and then refrained from eating for 24 hours followed by 24 hours of eating. The following day they fasted again.

All participants of the study were women who were overweight or obese, with a BMI in the 25–40 range, aged between 35 and 70. They followed a typical Australian diet consisting of 35% fat, 15% protein, and 50% carbohydrate.

“The most successful participants lost approximately 0.5 to 1 kg [~1 to 2 lbs] per week for each week of the study,” Hutchison says.

“This study is adding to evidence that intermittent fasting, at least in the short term, may provide better outcomes than daily continuous diet restriction for health and potentially for weight loss,” says Leonie Heilbronn, PhD, an associate professor from the University of Adelaide and SAHMRI. “While the study confirms that intermittent fasting is more effective than continuous diet restriction, the underlying signal for limiting people’s appetite, which could hold the key to triggering effective weight loss, requires further research.”

New trials now being undertaken will examine the efficacy of long-term fasting for both men and women.

— Source: University of Adelaide


Fruits and Vegetables May Be Important for Mental Well-Being

New research shows a positive association between the quantity of fruits and vegetables consumed and people’s self-reported mental well-being.

Specifically, the findings indicate that eating just one extra portion of fruits and vegetables a day could have an equivalent effect on mental well-being as around eight extra days of walking a month (for at least 10 minutes at a time).

A key feature of this work is that the study was able to follow the same individuals over time. The study also controlled for factors that may affect mental well-being, such as age, education, income, marital status, employment status, lifestyle, and health, as well as consumption of other foods such as bread or dairy products.

Neel Ocean, PhD, of England’s University of Leeds, who authored the study with Peter Howley, PhD, of the University of Leeds, and Jonathan Ensor, PhD, of the University of York, says, “It’s well established that eating fruit and vegetables can benefit physical health.

“Recently, newer studies have suggested that it also may benefit psychological well-being,” Ocean says. “Our research builds on previous work in Australia and New Zealand by verifying this relationship using a much bigger UK sample. While further work is needed to demonstrate cause and effect, the results are clear: People who do eat more fruit and vegetables report a higher level of mental well-being and life satisfaction than those who eat less.”

Howley says, “There appears to be accumulating evidence for the psychological benefits of fruits and vegetables. Despite this, the data show that the vast majority of people in the UK still consume less than their five-a-day. Encouraging better dietary habits may not just be beneficial to physical health in the long run but also may improve mental well-being in the shorter term.”

Ensor adds, “This work is part of a broader project between our universities known as “IKnowFood.” As well as investigating consumer behavior and well-being, IKnowFood is exploring how farmers in the UK, and businesses across the global food supply chain, can become more resilient in the face of growing uncertainty in markets, regulation, and the natural environment.”

— Source: University of Leeds