There was no significant difference between the groups in the studies regarding L-carnitina and flaxseed .
There is a lack of evidence regarding quality studies justifying the use of alternative products for weight loss
OBJECTIVE The high dem and for obesity treatment and conventional therapies ' lack of effectiveness increases the use of alternative products .
This study was aim ed at assessing evidence from r and omised clinical trials regarding the effectiveness of alternative weight-loss products ' ingredients .
Body fat loss achieved by stimulation of thermogenesis by a combination of bioactive food ingredients: a placebo-controlled, double-blind 8-week intervention in obese subjects
Background : A combination of tyrosine , capsaicin , catechines and caffeine may stimulate the sympathetic nervous system and promote satiety , lipolysis and thermogenesis . In addition , dietary calcium may increase fecal fat excretion . Objective : To investigate the acute and subchronic effect of a supplement containing the above mentioned agents or placebo taken t.i.d on thermogenesis , body fat loss and fecal fat excretion . Design : In total , 80 overweight – obese subjects ( ( body mass index ) 31.2±2.5 kg/m2 , mean±s.d . ) underwent an initial 4-week hypocaloric diet ( 3.4 MJ/day ) . Those who lost>4 % body weight were instructed to consume a hypocaloric diet ( −1.3 MJ/day ) and were r and omized to receive either placebo ( n=23 ) or bioactive supplement ( n=57 ) in a double-blind , 8-week intervention . The thermogenic effect of the compound was tested at the first and last day of intervention , and blood pressure , heart rate , body weight and composition were assessed . Results : Weight loss during the induction phase was 6.8±1.9 kg . At the first exposure the thermogenic effect of the bioactive supplement exceeded that of placebo by 87.3 kJ/4 h ( 95%CI : 50.9;123.7 , P=0.005 ) and after 8 weeks this effect was sustained ( 85.5 kJ/4 h ( 47.6;123.4 ) , P=0.03 ) . Body fat mass decreased more in the supplement group by 0.9 kg ( 0.5 ; 1.3 ) compared with placebo ( P<0.05 ) . The bioactive supplement had no effect on fecal fat excretion , blood pressure or heart rate . Conclusion : The bioactive supplement  increased 4-h thermogenesis by 90 kJ more than placebo , and the effect was maintained after 8 weeks and accompanied by a slight reduction in fat mass . These bioactive components may support weight maintenance after a hypocaloric diet
There was no significant difference between the groups in the studies regarding L-carnitina and flaxseed .
There is a lack of evidence regarding quality studies justifying the use of alternative products for weight loss
OBJECTIVE The high dem and for obesity treatment and conventional therapies ' lack of effectiveness increases the use of alternative products .
This study was aim ed at assessing evidence from r and omised clinical trials regarding the effectiveness of alternative weight-loss products ' ingredients .