In the news: Update on Intermittent Fasting; Fiber Fights Antibiotic Resistant Bugs

Intermittent Fasting & Weight Loss, AMD Risk

Intermittent fasting (IF) is a way of eating that involves periods of eating and fasting. The emphasis is not on what foods are consumed (hopefully healthy), but rather when they are eaten.

There are several different fasting methods. One, for example, is fasting for 24 hours once or twice weekly. Another, called the 8/16 method, involves skipping breakfast and restricting the daily eating period to 8 hours (e.g. 10-6 pm) then fasting for the next 16 hours.

The topic of IF, also called time-restricted eating, and weight control has been covered in previous Staying Healthy newsletters (see Sept. 2019 and Dec. 2016 issues at www.sbh.com). Now, a new clinical study(1)provides some evidence that time-restricted eating may help weight loss. And improve blood pressure too.

In this 14-week investigation, University of Alabama researchers focused on time-restricted eating in the earlier part of the day. The 8-hour time window for consuming food was 7:00 A.M. through 3:00 P.M. (then fasting for 16 hours) at least 6 days per week.

Ninety overweight or obese participants were randomly assigned to the 8/16 early time-restricted period group or a group that was allowed to eat over 12 hours or more. All the participants were counseled on weight loss and advised to eat fewer calories and to exercise roughly 1 ½ to 2 ½ hours per week. But both groups were on their own to follow that advice, and there were no differences between the groups in physical activity or calorie intake at the end of the study.

Both groups lost weight, but the 8/16 group dropped greater than 5 lbs. more – a meaningful amount. A closer look suggests that the 8/16 eating pattern was more effective at reducing body fat. Compared with controls, the 8/16 group also had reduced diastolic blood pressure, and greater improvements in mood, depression, vigor, and fatigue.

IF Benefits for Eye Health?

Another intriguing new study from Korean researchers suggests that IF may help reduce the risk of developing age-related macular degeneration AMD(2).

Looking at over 4,500 elderly people the researchers found that intermittent fasting by skipping breakfast was significantly associated with a lower risk of AMD (nearly 60% lower risk), especially in those less than 70 years old, people who were obese, and those living in urban rather than rural areas.

This is the first study to explore a link between IF and AMD risk. it would be important if a role for IF in AMD can be confirmed, but this is just the beginning.

Fiber May Help Fight Bad Bugs in the Gut

Whether or not you practice IF, it pays to include lots of fiber and a variety of foods in your diet according to a study by investigators at UC Davis(3).

Microbes that are resistant to commonly used antibiotics is a big problem, and one that’s only expected to grow. Antimicrobial resistance in people is largely based in their gut microbiome, where these microbes carry genetically encoded strategies to survive contact with antibiotics. The new study explored whether diet could affect the amount of antibiotic resistance microbes in people’s guts.

The researchers found that eating a diverse diet with at least 8-10 grams of soluble fiber and a lower intake of protein (especially from beef and pork) was linked to a lower level of antimicrobial resistant genes in the gut and higher levels of microbes that help dampen inflammation. But the most important predictor of low levels of antibiotic resistance microbes was eating a diverse diet of minimally processed plant foods (likely also fiber-rich). Soluble fiber is found in foods like grains, beans, nuts and some fruits and veggies.

References

1. Jamshed H, et al. Effectiveness of early time-restricted eating for weight loss, fat Loss, and cardiometabolic health in adults with obesity: A randomized clinical trial. JAMA, ePub Aug. 8, 2022.
2. Choi EY, et al. Intermittent fasting is associated with a decreased risk of age-related macular degeneration. Am J Ophthalmol. S0002-9394(22)00255. ePpub July 6, 2022.
3. US Agricultural Research Service. Diets high in fiber associated with less antibiotic resistance in gut bacteria, May 10, 2022.