How are changes in coffee and caffeine intake associated with changes in fat tissue?

A recent study published in Clinical Nutrition evaluated the associations between changes in coffee and caffeine consumption and fat tissue changes.

Background

Being overweight or obese elevates the risk of chronic diseases, such as cancer, depression, type 2 diabetes (T2D), and cardiovascular disease (CVD). Anthropometric measures are good surrogates for adiposity but fail to capture fat tissue/distribution. Dual-energy X-ray absorptiometry (DXA) can precisely determine and localize fat tissue.

DXA can provide more reliable assessments of the cardiometabolic risk of obesity. Regular coffee intake is inversely linked to the risk of CVD, some cancers, T2D, and mortality. Some of the benefits may result from the effects of coffee on energy metabolism, partly due to the metabolic actions of caffeine.

About the study

In the present study, researchers examined the relationship between changes in the consumption of coffee/caffeine with changes in adiposity measures. The team used data from the first three years of an ongoing six-year randomized clinical trial (PREDIMED-Plus) conducted in 23 centers across Spain. Older males aged 55 – 75 and females aged 60 – 75 were recruited if they were obese or overweight and met at least three criteria for metabolic syndrome.

The researchers used data from participants who underwent DXA scans. Participants indicated their dietary and lifestyle habits at baseline, six months, and every year. They also provided responses to a validated food frequency questionnaire comprising 143 items. Coffee consumption habits were stratified according to the presence/absence of caffeine.

At each visit, adherence to an energy-reduced Mediterranean diet (er-MedDiet) was assessed using a modified version of a validated 14-item questionnaire. The study outcomes were adiposity measured by DXA at baseline, six months, one year, and three years. Whole-body scans provided information on body composition distinguishing between body components (lean, bone, and fat mass) and their localization.

Fat tissue measurements differentiated between total body fat, visceral adipose tissue (VAT), android to gynoid fat ratio, trunk fat, and subcutaneous adipose tissue (SAT). One-way analysis of variance and chi-squared tests were performed to assess differences in sex- and age-adjusted variables by coffee intake categories. A two-level linear mixed-effects model was developed to examine the association between coffee intake changes and changes in DXA-derived adipose tissues.

Findings

The final sample comprised 1483 participants, with a relatively low mean level of caffeinated coffee intake. Individuals with an increased intake of caffeinated coffee were mostly males and likelier to be younger. In addition, a higher intake of salt, total energy, trans-unsaturated fatty acids, pure alcohol, higher prevalence of smoking, lower adherence to er-MedDiet, and more pronounced abdominal obesity were observed in individuals consuming more than one cup of coffee.

There were minor lifestyle differences between participants with high and low consumption of decaffeinated coffee, except for salt consumption. Body mass index (BMI), waist circumference, physical activity, and dietary patterns improved during the follow-up relative to baseline. The average coffee intake did not significantly change over time.

Lower body fat was evident for participants shifting from low to intermediate (moderate) coffee intake compared to those who maintained low consumption. Comparable results were obtained for changes in VAT or trunk fat. There were no significant associations for participants changing to a higher intake of caffeinated coffee.

Android-to-gynoid fat ratio and SAT were not associated with changes in the consumption of caffeinated coffee. Body mass index and waist circumference were not associated with changes in coffee intake. A stratified analysis by sex revealed a slightly stronger association between concurrent total/trunk fat changes and moderate caffeinated coffee consumption.  

No statistically significant results were observed between adiposity markers and decaffeinated coffee intake. Findings were similar when focused on caffeine intake from all food sources. Moreover, sensitivity analyses confirmed the robustness of the relationship between moderate intake of caffeinated coffee and fat tissues.

Conclusions

To conclude, the authors found that shifting from no/low to moderate consumption levels of caffeinated coffee was associated with a decline in VAT, trunk fat, and total fat in a Mediterranean cohort of older adults at high cardiovascular risk. Notably, the findings did not suggest a linear dose-response pattern.

Additionally, the team did not capture information on specific coffee blends. Decaffeinated coffee was not associated with adiposity markers. The findings suggest that moderate levels of caffeinated coffee consumption could become a part of the weight management strategy among older people with obesity.