ESPEN Congress Brussels 2005 Low carbohydrate or low fat diet to loose weight: Pro Low Fat Diets Arne Astrup
27th ESPEN Congress 28 August 2005 Low carbohydrate or low fat diet to loose weight: Pro Low Fat Diets Arne Astrup Head, professor, MD, dr.med.sci. Institute of Human Nutrition
Diets and obesity Hypocaloric reduced-fat diets for weight loss Reduced-fat diets for maintenance Role of non-fat component Low-carbdiets High protein, normal fat diets Conclusions
Nugenob Low or high fat diets for induction of weight loss 771 obese subjects of both gender (20-50 years) from 8 European centres were enrolled in a randomised, open label 10-weeks dietary intervention study comparing two different hypocaloric (-600 kcal/d) diets with the proportion of total calories from fat of 25 or 40. Petersen M, Taylor M, Saris W, Verdich C, Toubro S, MacDonald I, Sørensen, TIA, Astrup A. IJO (In press)
Changes in body weight Moderate fat Low fat group group (n=312) (n=336) Before kg) 100.7 (16.0)( 100.2 (16.9) After (kg) 94.1 (15.4) 93.3 (16.1)( ns Decrease (kg) 6.6 (3.5)( 6.9 (3.4) ns Petersen M, Taylor M, Saris W, Verdich C, Toubro S, MacDonald I, Sørensen, TIA, Astrup A. IJO (In press)
The proportion of subjects who lost 10% or more of initial body weight was higher in the low fat than in the moderate fat group (18 % vs. 12 %, P < 0.01). Petersen M, Taylor M, Saris W, Verdich C, Toubro S, MacDonald I, Sørensen, TIA, Astrup A. IJO (In press)
Results lipids, glucose and insulin moderate (n=312) and low-fat group (n=336) Decrease Diff. in change (95% CI) Low-fat Moderate-fat Total Chol (mmol/l) 0.36 (0.63) 0.25 (0.55) 0.10 (0.02-0.18) Total TAG (mmol/l) 0.04 (0.41) 0.19 (0.71) -0.09 (-0.16 (-0.03)) LDL Chol (mmol/l) 0.26 (0.57) 0.14 (0.50) 0.11 (0.03-0.18) HDL Chol (mmol/l) 0.08 (0.18) 0.04 (0.16) 0.04 (0.02-0.07) Insulin (µu/ml) 1.2 (4.9) 1.2 (5.9) 0.3 (-0.5-1.0) Glucose (mmol/l) 0.12 (0.49) 0.14 (0.48) -0.01 (-0.08-0.05) Petersen M, Taylor M, Saris W, Verdich C, Toubro S, MacDonald I, Sørensen, TIA, Astrup A. IJO (In press)
A typical long-term randomised ad lib Low-fat diet study Change in weight (kg) 3 0 Low adherence a A reduction in dietary fat from 35% ** to 25% of total -3 energy produced a High adherence mean weight loss of ** ** ** 3.3 kg after one year -6 0 Intervention 1 2 3 4 5 Years Swinburn et al. Diabetes Care 2001; 24: 619-24
3 Meta-analysis analysis of low-fat diets 3 identical outcomes in <12 months trials: Low-fat diets prevent weight gain in normal weight subjects and produce a modest but important weight loss in overweight subjects (3-4 kg) There exists a linear dose-response relationship between dietary fat-% and weight loss
The Lifestyle Heart Trial Dietary fat 10% of calories Exercise (ns), smoking cessation, stress coping One year: -16 kg vs -3 kg weight loss TG increase, but regression of coronary atherosclerosis 5 year: -5.8 kg vs. + 1.5 kg (no difference in physical activity) Less than half coronary events Ornish et al. Lancet 1990; 336: 129-33 Ornish et al. JAMA 1998; 280: 2001-7
Adverse effect of low-fat diets The non-fat component Carbohydrates sugar GI - soft drinks Protein Metabolic symdrome - inflammation
CARMEN Change in body weight ² weight (kg) 3 2 1 0-1 -2-3 p<0.05 p<0.001 SCHO CCHO CD CS group Saris, Astrup, Prentice et al. Int J Obes
The importance of the non-fat component Raben et al. Am J Clin Nutr 2002; 76: 721-9
Does sugar in soft drinks make you fat? Sugar versus sweetener Weight changes Kg 2,5 1,5 Sucrose Sweetener 20 % increase in TG in sucrose group vs. Control (AJCN in press) 0,5-0,5-1,5 Group x time, p < 0.001-2,5 0 2 4 6 8 10 Weeks Raben et al. Am J Clin Nutr 2002; 76: 721-9
Low-fat vs. Low-fat plus Gardner et al. Ann.Int.Med. 2005,145:725-9
Berry - Lancet The diet: < 30 % fat + 250-300 g fruit +125-150 g vegetables +25-50 g walnuts/almonds + 400-500 g whole grain Produced a 3 kg weight loss over 2 years Singh et al. Lancet 360, 1455,2002
Diabetes Prevention Program: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Goals for lifestyle treatment: 7 % weight loss ( maintained ) 25 E % from fat 1200 1800 kcal/day 150 min brisk walking/ week 16 sessions over 6 months, subsequently one session/month. Age 51 yr; BMI 34 kg/m 2 ; average follow-up 2.8 yr; average weight loss 7% after 1 yr and 5% for study duration
Figure 14: Successful weight loss with a hypo caloric-low fat diet and increased physical activity (n=3234) Weight loss (kg) 4 2 0-2 -4-6 Placebo -8 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Year of treatment Metformin Lifestyle
Figure 15: Reductions in the incidence of diabetes with a hypo caloric-low fat diet and increased physical activity Cumulative incidence of diabetes (%) 40 30 20 10 Placebo Metformin Lifestyle RR* 31% RR* 58% 0 0 1.0 2.0 3.0 4.0 Year of treatment *Reduction in risk of progressing to type 2 diabetes versus placebo
CRP predicts adverse effect on TG of 6 months high simple-cho diet 0.6 0.4 a, b, c, d 0.2 0.0 a b c d -0.2-0.4-0.6-0.8-1.0 Sim ple CHO Com plex CHO Control Brinkman Sørensen et al. (2004)
Diets and obesity Hypocaloric reduced-fat diets for weight loss Reduced-fat diets for maintenance Role of non-fat component Low-carbdiets High protein, normal fat diets Conclusions
Popular high-protein diet books
Low Carbohydrate vs Low Fat (Completers analysis) 0 Weight Loss (%) -5-10 Low-Fat Low Carb -15 0 3 6 9 12 Foster et al NEJM 2003; Months of Diet
Very similar weight loss, but higher drop-out in Ornish and Atkins
RDI: At least 130 g carbohydrate/day Atkits: 20-50 g/d Adverse effects: Muscle cramps, headache, weakness, diarheea etc. Astrup, Larsen, Harper. The Lancet. 2004; 364: 897-9.
Low-carb and physical performance
More adverse effects Novel presentation of coeliac disease after following the Atkins' low carbohydrate diet van Heel, DA; Dart, J; Nichols, S; Jewell, DP; Playford, RJ GUT, 54 (9): 1342-1342 SEP 2005
Conclusions on low-carb Low-carb diets produce greater initial weight loss than low-fat diets Risk factors are improved due to the weight loss Long-term weight loss is no better than low-fat Side effects headache, muscle cramps etc. due to carb-deficiency and dehydration Predicted long-term adverse effects: CHD and cancer
Energy density does matter Potatoes 450 g (3.6 kj/g) Avocado 260 g (7.7 kj/g)
Diets and obesity Hypocaloric reduced-fat diets for weight loss Reduced-fat diets for maintenance Role of non-fat component Low-carbdiets High protein, normal fat diets Conclusions
Proposed Hierarchy of Satiety Need hypothesis-driven studies to determine differences Protein leucine fructose fiber Carbohydrate mct sucrose Fat
Can more protein as part of a normal-fat diet improve weight loss? or
A randomized 6-month 6 trial on two fat-reduced diets: High CHO versus high protein High adherence can be achieved by providing all foods free of charge Skov AR et al. Int J Obes 2002; 23: 528-36
DIETARY INTAKE Baseline 0-6 mo 12 mo (n=50) P (n=46) P (n=41) P Energy (MJ/d) MP 9.9 (±0.5) NS 10.8 (±0.4) 0.001 8.2 (±0.4) NS HP 9.5 (±0.5) 9.0 (±0.4) 8.4 (±0.4) Protein (E%) MP 15.1 (±0.6) NS 12.0 (±0.1) <0.0001 13.9 (±0.4) <0.0001 HP 16.1 (±0.5) 24.3 (±0.1) 21.2 (±0.8) CHO (E%) MP 44.5 (±1.3) NS 58.6 (±0.2) <0.0001 54.7 (±1.8) 0.005 HP 45.6 (±1.1) 46.3 (±0.2) 48.9 (±1.2) Fat (E%) MP 40.3 (±1.2) NS 29.4 (±0.1) NS 31.4 (±1.6) NS HP 38.2 (±1.1) 29.5 (±0.2) 30.0 (±1.4) MP: Medium protein group HP: High protein group Due A et al. Int J Obes 2004;28:1283-90.
A randomized 12-month trial on two fat-reduced diets: High CHO versus high protein Urinary Nitrogen excretion 18 (n=23) Medium-protein High-protein Control 16 (n=23) 24-h UN (g) 14 12 10 (n=14) (n=22) (n=18) 8 6 0 1 2 3 4 5 6 7 8 9 10 11 12 Duration (month) Due, Toubro, Skov & Astrup, Int J Obes (in press)
A randomized 12-month trial on two fat-reduced diets: High CHO versus high protein Weight loss and fat loss Skov AR et al. Int J Obes 2002; 23: 528-36
Protein reduces Intra-abdominal fat (cm²) 0-5 -10-15 -20-25 -30-35 -40 P=0.002 6 12 P=0.03 Medium-protein High-protein
Conclusions Intervention studies have shown that replacement of carbohydrate by protein from meat and dairy products (<25% E) in ad libitum consumed fatreduced diets, improves weight loss. The effect has been attributed to the greater satiety and thermogenic effect of protein than carbohydrate. No adverse effects have been found on cardiovascular risk factors, kidney function, or bone health rather beneficial effects!
US recommendations AMDR (DRI, Institute of Medicine, USA) Protein: Adults: 10-35% Older children: 10-30% Smaller children: 10-20 %
Diet, Obesity and Genes European Commission 6 th framework: Food Quality & Safety Coordinator: Wim Saris (NUTRIM, Maastricht)