Obesity has become a global epidemic, with the World Health Organization (WHO) estimating that over 1.5 billion people would be overweight by 2015, leading to health costs exceeding $117 billion per year in the United States alone. While diet and lifestyle changes remain the cornerstone of obesity therapy, their long-term success is often limited and disappointing. Drug therapy, such as orlistat and sibutramine, has shown limited effectiveness, typically promoting only a 5% to 10% loss of total body weight. Consequently, there is a growing interest in natural ingredients as effective and practical remedies for obesity treatment due to their relative safety. This review aims to summarize the effects of astaxanthin on body weight management, drawing from scientific literature and recent publications.
Natural Products for Body Weight Management
Numerous natural products have been studied for their potential in body weight management. Among these, catechins, capsaicin, conjugated linoleic acid (CLA), fucoxanthin, soy isoflavones, glabridin, astaxanthin, and cyanidin-3-glucoside have shown promise. These natural products offer effective and safe alternatives for managing body weight.
Astaxanthin: A Potent Antioxidant Carotenoid
Astaxanthin is a natural antioxidant carotenoid found in various living organisms, including salmon, shrimp, crustaceans, and algae like Haematococcus pluvialis. It has garnered attention for its potential health benefits, including its effects on body weight control.
Animal Studies on Astaxanthin and Weight Loss
Recent animal studies have indicated that astaxanthin may have a beneficial effect on body weight control. One study divided fifty 4-week-old female ddY mice into five groups: a normal diet control group, a high-fat diet group (placebo), and three groups fed a high-fat diet supplemented with 1.2, 6, or 30 mg/kg body weight of astaxanthin. The results demonstrated that astaxanthin, at levels of 6 mg/kg or 30 mg/kg body weight, significantly reduced the body weight gain induced by the high-fat diet. Additionally, astaxanthin reduced liver weight, liver triacylglycerol, and plasma triacylglycerol, as well as total cholesterol levels.
Another study with a similar design from the same research group found that astaxanthin treatment stimulated an enhancement of fatty acid utilization in mice. These findings suggest that astaxanthin may play a role in reducing weight gain and improving lipid metabolism.
Read also: Weight Loss Guide Andalusia, AL
Astaxanthin and Non-Alcoholic Fatty Liver Disease (NAFLD)
Non-alcoholic fatty liver disease (NAFLD) and insulin resistance often coexist in individuals with obesity and type 2 diabetes, affecting a significant portion of the general population. Hepatic inflammation and fibrosis can result from excessive hepatic lipid accumulation followed by lipid peroxidation.
Astaxanthin has shown promise in preventing and reversing hepatic insulin resistance and NAFLD. It regulates macrophage and T-cell accumulation, as well as the M1/M2 status of macrophages/Kupffer cells in the liver of mice. Furthermore, astaxanthin has been shown to alleviate the progression of NAFLD in humans.
In a study involving high-fat diet-induced obese (DIO) and genetically obese (ob/ob) mice, astaxanthin administration reduced hepatic steatosis and triglyceride (TG) accumulation significantly, even though weight and adiposity were not affected. In vitro experiments with primary hepatocytes showed that astaxanthin, but not α-tocopherol (vitamin E), resulted in a dose-dependent decrease in TG accumulation. Further analysis revealed that astaxanthin reduced lipid accumulation by decreasing lipid uptake.
Astaxanthin's Impact on Dyslipidemia and Liver Dysfunction
In a study comparing the effects of astaxanthin and vitamin E on diet-induced NAFLD, astaxanthin decreased plasma TG, total cholesterol (TC), non-esterified fatty acid (NEFA), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels significantly in mice fed a high-fat, cholesterol, and cholate diet (CL). Vitamin E, on the other hand, tended to decrease TG and TC levels but did not affect NEFA, ALT, and AST levels. These results indicate that astaxanthin improved dyslipidemia and liver dysfunction in NAFLD mice.
Prevention of Hepatic Steatosis Through Lipogenic Gene Suppression
Astaxanthin has been shown to prevent the development of hepatic steatosis by suppressing lipogenic gene expression. During the development of steatohepatitis, the expression of lipogenic regulator genes, including Srebp1c, Lxra, Chrebp, and fatty acid synthesis genes, including Fasn and Scd1, was increased significantly in the livers of mice fed a CL diet. Astaxanthin treatment suppressed the expression of these lipogenic genes, whereas vitamin E did not alter or slightly decreased gene expression. Astaxanthin also downregulated the upregulated expression of Cd36 caused by the CL diet, suggesting that it suppresses lipogenesis and lipid uptake to reduce lipid accumulation in the liver of NAFLD/NASH mice.
Read also: Beef jerky: A high-protein option for shedding pounds?
Amelioration of Glucose Intolerance and Insulin Resistance
Astaxanthin has demonstrated the ability to improve glucose intolerance and insulin resistance in NAFLD mice. Glucose tolerance tests (GTTs) indicated that astaxanthin administration decreased blood glucose levels in normal chow-fed mice and suppressed CL diet-induced glucose intolerance and hyperinsulinemia. Insulin tolerance tests (ITTs) showed that astaxanthin-treated mice had slightly increased insulin sensitivity. These results were associated with enhanced insulin-stimulated phosphorylation of the insulin receptor (IR)-β subunit (p-IRβ) and Akt (p-Akt) in the livers of astaxanthin-treated mice. Furthermore, astaxanthin enhanced insulin signaling in palmitic-acid-loaded primary hepatocytes, protecting mice against diet-induced hepatic insulin resistance and glucose intolerance.
Reduction of Kupffer and Stellate Cell Activation
Astaxanthin has been found to reduce the activation of both Kupffer and stellate cells, attenuating hepatic inflammation and fibrosis. It markedly reduced the number of F4/80+ macrophages/Kupffer cells and decreased the expression of pro-inflammatory cytokines, including Tnf, Il6, and Il1b, which were upregulated by the CL diet. These findings were associated with the attenuated phosphorylation of JNK, p38 MAPK, and NF-κB p65, indicating that astaxanthin reduces the infiltration and activation of Kupffer cells to attenuate hepatic inflammation in NASH mice.
Astaxanthin Supplementation and Exercise Training in Obese Males
A study involving obese males investigated the effects of 12 weeks of high-intensity training with astaxanthin supplementation on adipokine levels, insulin resistance, and lipid profiles. Participants were divided into four groups: a control group (CG), a supplement group (SG), a training group (TG), and a training plus supplement group (TSG). The training protocol consisted of 36 sessions of high-intensity functional training (HIFT).
The results showed significant differences between the groups for all indicators, including levels of Cq1/TNF-related protein 9 and 2 (CTRP9 and CTRP2), and growth differentiation factors 8 and 15 (GDF8 and GDF15). Post-hoc analysis indicated that the levels of CTRP9, CTRP2, and GDF8 were different from the CG, although levels of GDF15 were similar to CG. Levels of GDF8 were similar in the SG and TG groups, with reductions of GDF15 levels in both training groups.
The study concluded that 12 weeks of astaxanthin supplementation and exercise training decreased adipokine levels, body composition (weight, %fat), anthropometrical factors (BMI), and improved lipid and metabolic profiles.
Read also: Inspiring Health Transformation
Astaxanthin and Maternal Diet
Maternal diet plays a critical role in regulating fetal growth and development. Studies have explored the impact of astaxanthin on the proteomic profile of adipose tissue in rats that underwent perinatal undernourishment.
Effects of Astaxanthin and Docosahexaenoic Acid (DHA)
One study evaluated the effect of astaxanthin (AsX) and docosahexaenoic acid (DHA) on the proteomic profile of rat adipose tissue that underwent perinatal undernourishment. The rats were divided into three groups: a control group, a perinatally undernourished group (Peri UN), and a perinatally undernourished group supplemented with AsX and DHA (Peri UN + AsX & DHA).
The results of the study provided insights into the potential of astaxanthin and DHA in mitigating the adverse effects of perinatal undernourishment on adipose tissue function.
Other Natural Products and Weight Management
Catechins
Catechins, found abundantly in green tea, have been shown to increase energy expenditure and fat oxidation. Studies have demonstrated that green tea extract can lead to modest weight loss and improved HDL-cholesterol and blood pressure.
Capsaicin
Capsaicin, the active ingredient in hot peppers, can promote calorie expenditure. Epidemiological data suggest that the consumption of foods containing capsaicin is associated with a lower prevalence of obesity.
Fucoxanthin
Animal studies have shown that fucoxanthin has anti-obesity activity, possibly through mitochondrial uncoupling protein 1 (UCP1) expression in white adipose tissues (WAT).
Soy Isoflavones
Soy isoflavones may be beneficial for the prevention of obesity and diabetes by affecting glucose and lipid metabolism. Studies have shown that soy isoflavones can reduce fat mass and body mass index in postmenopausal women.
Conjugated Linoleic Acid (CLA)
Conjugated linoleic acid (CLA) has demonstrated anti-obesity effects in animal studies. It can decrease body fat and increase lean body mass. In humans, CLA may reduce body fat mass.
Glabridin
Glabridin, the major flavonoid of licorice, has shown abdominal fat-lowering and hypoglycemic effects. Studies have indicated that licorice flavonoids can suppress body weight gain and decrease blood glucose levels.
Cyanidin-3-Glucoside
In mice, cyanidin 3-glucoside-rich purple corn color (PCC) has been shown to suppress high-fat diet-induced increases in body weight gain and adipose tissue weights.
tags: #astaxanthin #and #weight #loss #studies