Purple sweet potato, body fat and inflammation in obese rats
What it found
In obese rats, purple sweet potato powder added to a high-fat diet reduced body weight, visceral fat and fat cell size, and lowered signs of inflammation in fat tissue.
The study was done in animals, not people.
What they found
Animal and lab studies
Body weight and fat
Rats on the high-fat diet gained 23.6% more weight than controls. Those given purple sweet potato powder had 76.5% less weight gain than the high-fat group, and less fat around the kidneys and intestines.
Fat cell size
Fat cells in both belly and under-skin fat were larger in the high-fat group. Purple sweet potato powder reduced fat cell size, with a bigger effect on visceral (belly) fat.
Cholesterol and blood sugar
Total cholesterol was significantly lower in the purple sweet potato group compared to the high-fat group. Blood sugar and other cholesterol measures did not differ significantly.
Inflammation in fat
The high-fat diet raised inflammatory proteins TNF-α, IL-6 and MCP-1 in fat tissue. Purple sweet potato powder lowered these proteins in both belly and under-skin fat.
Fat browning
Purple sweet potato powder increased proteins linked to fat browning (FNDC5, PGC-1α, UCP-1) in fat tissue, especially in visceral fat. This suggests more energy burning.
What the authors conclude
“In conclusion, PSP effectively reduced visceral fat accumulation, attenuated inflammation, and promoted adipocyte browning.”
Also in their conclusions
- They say purple sweet potato supplementation significantly reduces body weight, visceral fat accumulation, and adipocyte size while modulating key molecular pathways involved in lipogenesis, inflammation, and adipose tissue browning.
- They suggest that purple sweet potato has the potential to be a valuable dietary intervention for the prevention and treatment of obesity and its related metabolic disorders.
- They call for further studies to elucidate the long-term effects of purple sweet potato and its applicability in human populations.
How it was done
Visceral fat is linked to inflammation and metabolic problems, and purple sweet potato contains anthocyanins that may help. The authors wanted to see how a simple dried powder affects body fat, inflammation and fat browning in obese rats.
Five-week-old male rats were fed a high-fat diet for 2 weeks to make them obese, then split into groups that got the high-fat diet alone, the diet with 5% purple sweet potato powder, or the diet with atorvastatin for 19 more weeks. There were 5 rats per group.
What it can’t tell you
- This was a study in rats, so it cannot show what happens in people.
- The study used a single dose of purple sweet potato powder, so it cannot show whether different amounts would have different effects.
- The authors note that the 19-week duration may not capture long-term effects.
Who paid
- Conflicts
- The authors declare no competing financial interest.
- Authors work at
- Chung Shan Medical University Hospital, Taiwan; Chung Shan Medical University, Taiwan; E-Da Cancer Hospital, Taiwan
The paper
- Title
- Purple Sweet Potato Ameliorates High-Fat Diet-Induced Visceral Adiposity by Attenuating Inflammation and Promoting Adipocyte Browning
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Yen CH, Chiang MH, Lee YC, Kao ES, Lee HJ (2025). Purple Sweet Potato Ameliorates High-Fat Diet-Induced Visceral Adiposity by Attenuating Inflammation and Promoting Adipocyte Browning. Journal of agricultural and food chemistry. doi:10.1021/acs.jafc.4c08799Free full textPubMed 39895065DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error