Does beer consumption cause beer belly?

Transcription

1 Does beer consumption cause beer belly? Nathalie Tommerup Bendsen, PhD Department of Human Nutrition Faculty of Life Sciences University of Copenhagen 8 April 2011 [1]

2 Beer belly myth or fact? Does beer intake increase the risk of overweight / obesity? abdominal fatness? Does intake level matter? 8 April 2011 [2]

3 What is beer? Main ingredients of most beers are: Water, Barley, Hops and Yeast. Nutrient content of beer (per 100 g, pilsner type): - Energy : ~45 kcal Sweet 7.4 kcal per gram - Alcohol: ~4-5 g taste - Several carbohydrates (sugars and dextrins): ~3 g - Small amount of protein: <0.1 g - Fiber: ~0.6 g - B-vitamins, especially B6 (pyridoxine) & B9 (folate) - Minerals: magnesium, potassium & silicon - Numerous trace compounds: polyphenols, flavonoids and isohumulones Bitter taste 8 April 2011 [3]

4 What is beer? Per 100 ml Main ingredients of most beers are: Water, Barley, Hops and Yeast. 8 April 2011 [4] Nutrient content of beer (per 100 g, pilsner type): - Energy : ~45 kcal Sweet 7.4 kcal per gram - Alcohol: ~4-5 g taste - Several carbohydrates (sugars and dextrins): ~3 g - Small amount of protein: ~350 ml <0.1 g - Fiber: ~0.6 g - B-vitamins, especially ~150 B6 ml (pyridoxine) & B9 (folate) - Minerals: magnesium, potassium & silicon ~40 ml - Numerous trace compounds: polyphenols, flavonoids and isohumulones Wannamethee, Beer in health and disease prevention, 2009 Bitter taste

5 Why should beer intake promote fatness? Alcohol metabolism & fat oxidation Liquid energy & satiety Alcohol & appetite 8 April 2011 [5]

6 8 April 2011 [6] Do alcohol calories count?

7 Alcohol intake decreases fat oxidation Suter et al. NEJM April 2011 [7]

8 Liquid energy & satiety Meal-replacement shake vs. nutrition bar Leidy et al. Obesity April 2011 [8]

9 Beer (& wine) increases appetite and energy intake Westerterp-Plantenga & Verwegen, AJCN April 2011 [9]

10 Are alcohol calories compensated for? Mattes. Physiololy and Behaviour April 2011 [10]

11 Why should beer intake promote abdominal fatness? Alcohol stimulates production of cortisol + Alcohol decreases lipid oxidation Central obesity Adinoff et al. Alcoholism: Clin Exp Res 2005 Suter et al. NEJM 1992 Purnell et al. AJP April 2011 [11]

12 Systematic review: What is the evidence for a fattening effect of beer? Records identified through databases (n = 2811) Full-text articles assessed for eligibility (n = 70) Records identified through other sources (n = 11) Full-text articles excluded (n = 25) Studies included in qualitative review (n = 45) Observational studies (n = 34) Intervention studies (n = 11) Not included in syntheses (n = 22) Studies included in quantitative synthesis Intervention studies (n = 10) Beer vs non-alcoholic beer (n = 6) Beer vs. control (n = 4) Studies included in dose-response graphs: Observational studies (n = 14) Prospective analyses (n = 5) Cross-sectional analyses (n = 10) 8 April 2011 [12]

13 Observational studies: Association between beer intake and fatness Women Men Overall fatness (BMI/weight) Abdominal fatness (WC/ WHR) Overall fatness (BMI/ weight) Abdominal fatness (WC/ WHR) positive association Cross-sectional studies Prospective studies no association Cross-sectional studies Prospective studies negative association Cross-sectional studies 8 April 2011 [13] Prospective studies

14 Is there a dose-response relationship? Our expectation Waist circumference 8 April 2011 [14]

15 Cross-sectional studies: Are beer-drinkers fatter? Body mass index Waist-hip ratio Waist circumference 16 glasses/wk 8 April 2011 [15]

16 Prospective studies: Does beer consumption increase the risk of future weight or waist gain? Body weight change Waist change 8 April 2011 [16]

17 Intervention studies: Alcoholic beer vs low-alcoholic beer vs wk g/day ethanol ~ L alcoholic beer 8 April 2011 [17] A 0.7 kg higher body weight after alcoholic beer compared to low- or non-alcoholic beer

18 Intervention studies: Alcoholic beer vs no alcohol vs wk g/day ethanol ~ L alcoholic beer 8 April 2011 [18]

19 Conclusions Few studies have been conducted with the objective to assess whether beer intake is associated with body fatness Results are inconsistently presented across studies Most studies are of low quality Limited scientific evidence to support that beer intake is responsible for the beer belly High beer intakes (>4 L or 16 gl/wk) may be associated with a higher degree of abdominal adiposity 8 April 2011 [19]

20 Possible explanations for inconsistent findings Underreporting of beer intake Are excessive drinkers included in research studies? Drinking pattern Lifestyle Physical activity Diet Smoking Education 8 April 2011 [20]

21 Beer-drinking and lifestyle I Johansen et al. BMJ April 2011 [21]

22 Beer-drinking and lifestyle II Germany 7876 men Schütze et al. EJCN April 2011 [22]

23 Beer goggles 80 university students were asked to rate the attractiveness of unfamiliar faces (photos) of the opposite sex Results: Attractiveness ratings were positively correlated with blood alcohol concentration Conclusion: Beer increases attractiveness ratings for opposite sex faces Lyvers et al. Soc Psychol April 2011 [23]

24 Thank you for your attention. Questions? The Dutch Beer Knowledge Institute provided financial support for the execution of this work. 8 April 2011 [24]

25 Beer and mortality Castelnuovo et al., Arch Int Med April 2011 [25] 22% CHD risk reduction among beer drinkers (95% CI: 14-30%) Castelnuovo et al., Circulation 2002 HDL-cholesterol Adiponectin Fibrinogen Brien et al., BMJ 2011 Insulin sensitivity Blood pressure

26 Alcohol and risk of type 2 diabetes A meta-analysis: ~ subjects followed for 12 y RR of T2D Koppes et al. Diabetes Care April 2011 [26]