1.
Flaxseed dietary fiber supplements for suppression of appetite and food intake.
Ibrügger, S, Kristensen, M, Mikkelsen, MS, Astrup, A
Appetite. 2012;(2):490-5
Abstract
UNLABELLED We conducted two single-blinded randomized crossover acute studies with 24 and 20 subjects, respectively, to compare (I) CONTROL vs. Flax drink; and (II) Flax drink vs. Flax tablets. The subjects were exposed to one of the treatments after an overnight fast, and rated appetite sensation for 120 min using visual analog scales (VAS). Hereafter they consumed an ad libitum early lunch to assess energy intake. The treatments were iso-caloric and iso-volumeric: CONTROL 300 mL drink; Flax drink: CONTROL drink with addition flax fiber extract (2.5 g of soluble fibers); and Flax tablet: CONTROL drink with flax fiber tablets (2.5 g of soluble fibers). Flax drink increased sensation of satiety and fullness compared to CONTROL and a significant decrease in subsequent energy intake was observed after the Flax drink compared to CONTROL (2937 vs. 3214 kJ). Appetite ratings were similar for Flax tablets and Flax drink as they did not differ by more than 1-4%. Subsequent energy intake was similar after the two treatments (3370 vs. 3379 kJ). A small dose of flaxseed fiber significantly suppresses appetite and energy intake. Furthermore, flaxseed fibers administered as drinks or tablets produce similar responses.
2.
The effect of caffeine, green tea and tyrosine on thermogenesis and energy intake.
Belza, A, Toubro, S, Astrup, A
European journal of clinical nutrition. 2009;(1):57-64
Abstract
OBJECTIVES To investigate the effect of three different food ingredients tyrosine, green tea extract (GTE) and caffeine on resting metabolic rate and haemodynamics, and on ad libitum energy intake (EI) and appetite. METHODS Twelve healthy, normal weight men (age: 23.7 +/- 2.6 years, mean +/- s.d.) participated in a four-way crossover, randomized, placebo-controlled, double-blind study. Treatments were administered as tablets of 500 mg GTE, 400 mg tyrosine, 50 mg caffeine, or placebo, and were separated by >3-day washout. The acute thermogenic response was measured in a ventilated hood system for 4 h following ingestion. Blood pressure, heart rate (HR), and subjective appetite sensations were assessed hourly and ad libitum EI 4 h post-dose. RESULTS Caffeine induced a thermogenic response of 6% above baseline value (72 +/- 25 kJ per 4 h, mean +/- s.e.) compared to placebo (P<0.0001). The thermogenic responses to GTE and tyrosine were not significantly different from placebo. Tyrosine tended to increase 4-h respiratory quotient by 1% compared to placebo (0.01 +/- 0.005, P=0.05). Ad libitum EI was not significantly different between treatments but was reduced by 8% (-403 +/- 183 kJ), 8% (-400 +/- 335 kJ) and 3% (-151 +/- 377 kJ) compared to placebo after intake of tyrosine, GTE and caffeine, respectively. No significant difference in haemodynamics was observed between treatments. CONCLUSIONS Only caffeine was thermogenic in the given dose and caused no haemodynamic side effects. The sample size was probably too small to detect any appetite suppressant properties of the treatments. Further investigations are required.