Fucoxanthin is a compound (carotenoid) found in brown seaweed. It is known for its potential to combat a variety of health issues including obesity, diabetes, and inflammation. Read ahead to discover the benefits and side effects of fucoxanthin.
What Is Fucoxanthin?
Fucoxanthin is a carotenoid (a compound found in plants responsible for yellow, orange, or red color). The structure of fucoxanthin makes it different from other plant carotenoids (it has an unusual allenic bond, a 5,6-monoepoxide, and 9 conjugated double bonds).
Though its structure makes fucoxanthin unique, that also contributes to its instability. This instability makes it difficult to study fucoxanthin. However, the same instability is exactly what gives it the potential to help with health issues such as obesity, diabetes, inflammation, and cancer .
Mechanisms of Action
Fucoxanthin potentially has an anti-obesity effect by influencing gene expression of the following genes related to fat metabolism (in rats) :
- Acetyl-CoA carboxylase (ACC)
- Fatty acid synthase (FAS)
- Glucose-6-phosphate dehydrogenase (G6PDH)
- Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA)
- Acyl-CoA cholesterol acyltransferase (ACAT)
1) Fucoxanthin May Help With Weight Loss
In a study (DB-RCT) of 151 obese, non-diabetic women with non-alcoholic fatty liver disease, fucoxanthin (0.8 mg to 4.0 mg) and pomegranate seed oil increased weight loss and reduced body and liver fat .
In mice on high-fat diets, fucoxanthin increased weight loss .
2) Fucoxanthin May Potentially Help With Depression
3) Fucoxanthin May Be Anti-Malarial
4) Fucoxanthin May Potentially Fight Aging
In mice treated with ultraviolet radiation, fucoxanthin applied to the skin blocked the premature aging of skin .
In skin cells, fucoxanthin protected against sunburn caused by ultraviolet radiation .
5) Fucoxanthin May Protect the Brain
In mice with traumatic brain injury, fucoxanthin reduced brain cell death .
6) Fucoxanthin May Reduce Inflammation
This effect was also seen in cell studies .
7) Fucoxanthin May Have Anti-Diabetic Effects
In a study on mice on high-fat diets, fucoxanthin reduced insulin resistance, which is a large factor in diabetes .
8) Fucoxanthin May Reduce Cholesterol and Triglycerides
9) Fucoxanthin May Protect Against Oxidative Stress
10) Fucoxanthin May Potentially Have Anti-Cancer Effects
11) Fucoxanthin Combats Bone Disease
In cells, fucoxanthin blocked the development of osteoclasts, a type of cell that helps break down bone to restore calcium to the blood. It also had anti-osteoporosis effects in mice with their ovaries removed .
12) Fucoxanthin May Potentially Benefit the Heart
Although fucoxanthin has no proven side effects in humans (possibly due to the limited number of human trials), in mice, it increased cholesterol levels. However, it didn’t have negative effects on the kidney, liver, spleen, and gonads or cause any cellular mutations in the mice [29, 30].
Limitations and Caveats
A limitation to fucoxanthin research is the lack of human trials, as almost all of the studies mentioned were conducted on animal models.
Inhibiting the activity of CYP3A4 can have two different effects on drug metabolism.
It can decrease the inactivation or degradation of the drug, and thus, increase the actual dose of the active form in the blood, which often causes unfavorable and long-lasting effects .
Or, it can decrease the activation of medications that are administered as a pro-drug, and thus, decrease the actual dose of the active form of the drug that reaches the blood, which lowers the biological efficacy of the drug .
The following drugs are likely affected by fucoxanthin and thus, consumption should be discussed with your doctor if you take these medications:
- Opioids: sufentanil  and methadone 
- Immunosuppressants: cyclosporine , tacrolimus , and sirolimus 
- Antihypertensive drugs: felodipine  and nifedipine 
- Anticancer drugs: endoxifen , tamoxifen , and sunitinib 
- Sedatives: midazolam 
- Cholesterol-lowering drugs (statins): simvastatin , atorvastatin, and lovastatin 
- Antibiotics: erythromycin 
- Corticosteroids: fluticasone propionate 
- Brown algae
The only human trial mentioned used a dosage of 0.8 – 4.0 mg fucoxanthin combined with pomegranate seed oil, which caused no adverse effects .
Users say fucoxanthin patches work well to increase weight loss and increase energy. However, some users believe the patches don’t work fast enough and don’t help with decreasing appetite.
Many users taking fucoxanthin pills believe they work well in reducing weight without needing to physically exercise.