Cruciferous Veggies Might Fight Fatty Liver
Health-Promoting Walnuts

Veggie Compound May Help Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a common condition where excess fat accumulates in the liver of those who drink little or no alcohol. NAFLD has, in fact, become a global epidemic. Leading risk factors for fatty liver include:obesity/overweight, type 2 diabetes, high cholesterol or having had gastric by-pass surgery.

Although it rarely causes symptoms, the condition has gained attention because, over time, NAFLD can lead to serious problems: liver damage and increased risk for liver cancer. Obesity can trigger inflammation and worsen liver damage in those with liver disease.

Shedding excess weight and eating healthfully is one reliable way to combat fatty liver. In addition, a new study (1) suggests that compounds found in cruciferous vegetables might be helpful in fighting NAFLD.

Cruciferous veggies include Brussels sprouts, broccoli, cauliflower, kale, cabbage, and bok choy. These Crucifers are rich in indole – a compound that’s also produced by a variety of bacteria residing in our gut.

In a new, multi-level study, researchers from Texas A&M aimed to understand whether indole impacts fatty liver – and how it might do so – by investigating indole’s effects in people, animal models and individual cells.

The investigators looked at circulating levels of indole in 137 subjects and found lower levels in those with higher body mass index (BMI). Indole levels in people who were clinically obese were significantly lower than in lean individuals. Importantly, the team saw higher amounts of fat in the livers of obese people with lower levels of indole.

In experiments with mice fed high-fat diets to promote NAFLD, treatment with indole led to significantly less inflammation and fat accumulation in the liver.

The researchers also examined how indole affects individual cells. Adding indole to cultured cells resulted in the expression of a gene that regulates glucose breakdown, and stifled activation of pro-inflammatory immune cells (macrophages).

Shannon Glaser, PhD, professor, Texas A&M Health Science Center, said that in addition to reducing the amount of fat in liver cells, indole also acts on cells in the intestine, which send out signals that dampen inflammation (2). In future research, the team hopes to examine what healthy foods can alter gut microbiota and increase indole production in the future.

New Research Findings on Walnuts

While all nuts are welcome additions to a low saturated fat diet, walnuts with their high antioxidant and healthy fat content are one of the healthiest choices. Results from two new studies suggest that walnuts promote healthy gut bacteria and are linked to slower cognitive decline in at risk older people.

In the first study (3), Penn State researchers randomly assigned overweight participants to diets that replaced some of the saturated fat from a typical American diet with walnuts; or with vegetable oils (omega-3 alpha linolenic acid, the mono-unsaturate oleic acid).

The walnut group showed increases in gut bacteria that have been linked to improvements in some cardiovascular disease risk factors. Increases in the species Eubacterium eligens was associated with lower blood pressure measurements.

Researchers from Spain and California teamed in the second study (4) to see whether including 1-2 oz. walnuts in the daily diet of the elderly for 2 years could affect cognitive decline vs. a group that did not consume the nuts. While walnuts had little effect on cognition in the group overall, testing (fMRI) and further analysis suggest that walnuts might delay cognitive decline in those at higher risk – those who had lower initial cognitive test scores and who had smoked more

References

1. Linqiang M, et al. Indole alleviates diet-induced hepatic steatosis and inflammation in a manner involving myeloid cell PFKFB3. Hepatol. Epub ahead of print, Jan. 17, 2020.
2. Texas A&M AgriLife Communications. Natural compound in vegetables helps fight fatty liver disease. Feb. 6, 2020.
3. Tindall AM, et al. Walnuts and vegetable oils containing oleic acid differentially affect the gut microbiota and associations with cardiovascular risk factors: follow-up of a randomized, controlled, feeding trial in adults at risk for cardiovascular disease. J Nutr.
4. Sala-Villa A, et al. Effect of a 2-year diet intervention with walnuts on cognitive decline. The Walnuts And Healthy Aging (WAHA) study: a randomized controlled trial. Am J Clin Nutr Epub ahead of print, Jan. 7, 2020.