Deneo-Pellegrini H, et al. Food groups and risk of prostate cancer: a case-control study in Uruguay. Cancer Causes Control. 2012;23:1031-1038.
This case-control study evaluated 326 men age 40–89 y with verified and mostly advanced prostatic adenocarcinomas between 1996 and 2004. Both cases and controls answered a detailed questionnaire including sociodemographic variables, occupational exposures, family cancer history, tobacco history, alcohol consumption, and diet. The food-frequency questionnaire included 64 food items, representing the typical Uruguayan population diet. A total of 27 food items, including mate, were analyzed for their potential relationship with prostate cancer. A direct, positive association with risk of prostate cancer was found for mate consumption (OR, 1.96; 95 % CI, 1.17–3.31, P for linear trend =.005), while coffee, tea, and soft drinks were not associated with increased risks. This study echoes other epidemiologic studies that have shown increased risks of various cancers with chronic mate consumption.
Harrold JA, et al. Acute effects of a herb extract formulation and inulin fibre on appetite, energy intake and food choice. Appetite. 2013;62:84-90.
A patented herbal extract containing yerba mate, guarana and damiana (YGD) was evaluated alone, or in combination with soluble fermentable fibre (SFF) in this double-blind, placebo-controlled, crossover study. The fibre used was chosen because of previously observed effects on appetite. Participants were 58 normal-to-slightly overweight women who consumed a prescribed breakfast (496 kcal) followed 4h later by an ad libitum lunch. Fifteen minutes before meals, subjects took 3 YGD tablets and SFF (5g in 100mL water), YGD and water (100 mL), 3 placebo tablets and SFF, or 3 placebo tablets and water. Appetite was assessed using visual analogue scales, and energy intake was measured at lunch. Significant reductions in food and energy intake were observed with YGD (59.5g, 16.3%; 112.4kcal, 17.3%) and SFF (31.9g, 9.1%; 80kcal, 11.7%) compared with conditions where products were absent. Lowest intakes (gram and kcal) were in the YGD+SFF group. Significant reductions in AUC hunger and AUC desire to eat were also observed with the YGD+SFF combination. These preliminary data suggest that YGD can produce short-term reductions in caloric intake and the effect can be augmented by adding SFF. However, more study is needed to confirm actual efficacy as well as safety with long-term use.
Conforti AS, et al. Yerba mate (Ilex paraguariensis) consumption is associated with higher bone mineral density in postmenopausal women. Bone. 2012;50:9-13.
In this retrospective study among participants in a program for osteoporosis prevention and treatment, 146 postmenopausal women who drank ≥1 L of mate tea daily for ≥4 years were identified and matched by age and time since menopause with women who did not drink mate. Bone mineral density (BMD) was measured in both groups by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and femoral neck. Lumbar spine BMD in the mate group was 9.7% higher (0.952 g/cm2 vs 0.858 g/cm2: P<.0001); femoral neck BMD was 6.2% higher (0.817 g/cm2 vs 0.776 g/cm2; P=.0002). In multiple regression analysis, mate tea drinking was the only factor other than BMI that showed a positive correlation with BMD at both lumbar spine (P<.0001) and femoral neck (P=.0028). These results are a preliminary suggestion that long-term ingestion of mate may protect against bone loss, but confirmatory studies are needed. In addition, this benefit may be offset by the association that long-term chronic mate use has with increased risks for various cancers.