The ocean is awash in many healthy foodstuffs used across the globe, both animal and vegetable. Seaweed, for instance, is a mainstay of Asian cuisine, particularly in Japan and Korea, where a variety called wakame is used in soups like miso and Miyeok guk. And wakame and hijikia, known in the Latin as Undaria pinnatifida and Hijikia fusiformis, respectively, are brown sea vegetables imbued with high concentrations of heart-healthy omega-3 fatty acids. They also contain a substance called fucoxanthin.
As a marine carotenoid, fucoxanthin is inherently exceptional at fighting free radicals — rogue molecules that are created as a normal part of metabolism and roam the body, pilfering electrons from healthy cells. By stopping these free radicals and preventing electron theft, carotenoids stymie the ensuing DNA damage in healthy cells, which in turn is believed to help prevent chronic illness like cancer and heart disease. In addition to its free-radical-fighting power, fucoxanthin is emerging as the new darling of the supplement industry because of its fat-fighting potential.
The New Wave
Fucoxanthin is relatively fresh to the weight-management scene but is gaining popularity for its effects on body composition. Dozens of preliminary studies in animals have elucidated its effects, and although human research is still lacking, one study did show that it helps overweight people with weight loss. Reported in the January 2010 issue of Diabetes, Obesity and Metabolism, the 16-week study was conducted in “gold standard” fashion — meaning it was double-blinded, placebo-controlled and randomized. The 151 women studied were obese but nondiabetic; 113 of them had liver fat content above 11 percent, which indicates nonalcoholic fatty liver disease (NAFLD), and 38 had normal liver fat (NLF) content of below 6.5 percent.
The supplement used in the research, called Xanthigen, is a combination of 300 milligrams of brown seaweed extract, standardized for fucoxanthin content, and 300 milligrams of pomegranate seed oil. Results showed that the women in the NAFLD and NLF groups who took the supplement lost a significant amount of weight and body fat, had decreased liver fat content and liver enzymes, and saw an increase in their resting energy expenditure. The researchers noted that weight loss and reductions in body and liver fat content occurred earlier in the subgroup of NLF women.
The question that researchers are focusing on now is how fucoxanthin works. As a rule, laboratory and animal tests must be conducted before full-scale human trials. These types of preliminary studies of fucoxanthin have created excitement in the natural-products industry because of the positive results.
Researchers out of Hokkaido University in Japan reported in September 2007 in the Journal of Agricultural and Food Chemistry that animals fed a diet of 0.2 percent fucoxanthin for four weeks gained significantly less weight than animals on a control diet. Interestingly, this effect was more pronounced when the animals received a combination of fucoxanthin and fish oil. More specifically, the animals in the Japanese study gained less white adipose tissue — the main form of fat that mammals use for energy stores — than the mice on the control diet.
A report in the December 2009 Molecular Nutrition & Food Research indicates fucoxanthin may promote positive changes in body composition — despite eating a high-fat diet. Researchers at Kyungpook National University in South Korea showed that animals fed a diet of either 0.05 percent or 0.2 percent fucoxanthin had significantly lower bodyweight and fat accumulation compared with the control group, despite the fact that all the animals were put on a 20 percent fat diet.
In both studies, fucoxanthin was shown to increase UCP1 concentrations in white adipose tissue, which may be one reason it’s effective for reducing body-fat mass. UCP1 — formally known as the mitochrondrial uncoupling protein — is responsible for sparking nonshivering thermogenesis to prevent hyperthermia by burning fat stores for heat energy. Genetically or pharmaceutically forcing an increase in UCP1 levels is proven to burn off excess fat and reduce obesity.
Another team of researchers at Hokkaido University suggested that fucoxanthin may have a different mechanism of action than increasing UCP1 concentrations. Their November 2009 online report in the European Journal of Nutrition showed that fucoxanthin, and its metabolite fucoxanthinol, suppress triglyceride absorption. Biologically speaking, white adipose tissue is 60 percent to 85 percent lipid, with 90 percent to 99 percent of that being composed of triglycerides.
There is also evidence that fucoxanthin and fucoxanthinol may keep immature fat cells called preadipocytes from reaching maturity. The carotenoids do this by preventing the empty preadipocytes from filling up with lipid, according to research in a 2006 International Journal of Molecular Medicine. Researchers tested the effects of fucoxanthin and fucoxanthinol on a specific type of immature fat cells called 3T3-L1 preadipocytes. They showed that fucoxanthin inhibited lipid accumulation in the cells and that it was metabolized into fucoxanthinol inside these cells.
Dive Into the Benefits
Fucoxanthin’s preliminary performance in research to date certainly provides plenty of fodder for the scientific world to continue investigating its effects in people, but the news thus far is good for those seeking an edge in slimming down. The preliminary trials of fucoxanthin show promise for its anti-fat activity and have gone a long way to explain how it works — from acting as a thermogenic to inhibiting triglyceride absorption to preventing immature fat cells from plumping up to full maturity.
Fucoxanthin may be a newcomer to the weight-management scene, but this oceanic extract is making big waves.
Turning the Tide
In addition to promoting weight and fat loss, fucoxanthin may have other health benefits in the battle against these three afflictions.
Cancer: Fucoxanthin and its metabolite, fucoxanthinol, induce apoptosis (cell death) in several lines of human cancer cells, including breast, prostate and colon cancers, as well as leukemia.
Diabetes: In an animal model of diabetes, dietary fucoxanthin effectively decreases blood glucose and plasma insulin concentrations. Researchers have suggested that fucoxanthin’s effects on UCP1, a protein that affects thermogenesis, may be the reason for its ability to improve insulin sensitivity.
Metabolic syndrome: The multifunctional activities of fucoxanthin, including stimulating thermogenesis, reducing blood glucose and plasma insulin, and increasing liver concentrations of the omega-3 docosahexaenoic acid, make it potentially useful for preventing metabolic syndrome, a group of factors that increase the risk for coronary artery disease, stroke and Type 2 diabetes.