Ray mentioned many times that he favored fiber sources with a higher percentage of insoluble fiber, like carrots, mushrooms, and bamboo shoots. He had this view because of the studies he read, with certain soluble fibers having carcinogenic or inflammatory properties on longer time frames due to their tendency to promote certain bacterial populations. Not sure why you would say he only recommended carrots, when he recommended all 3 many different times. Also, carrots exist in many colors, including white if that’s your preference.Practically, it all boiled down to eating carrots. Which may help in the short-term for some things, but is not helpful for the issues people are dealing with nowadays. Carrots are inherently toxic due to the large amount of beta-carotene. One medium carrot has 5mg beta-carotene. The absorption rates vary. When adding fat like coconut oil, the amount of beta-carotene absorbed can be very large, it's possible to receive 1mg of retinol from this. This is already more than the RDA.
It's a bit tragic that the one fiber vegetable he discovered for speeding up bowel movements was also the one with the highest carotene content.
He also thought that coffee consumption and caffeine protected the liver, which is likely true, but he was not aware of the complex interactions of coffee with the detoxification of retinol.
Some links:
“We observed that carotenoids in the orange carrots reduced HFD-induced weight gain, better than white carrots. Histological and triglyceride (TG) analyses revealed significantly decreased HFD-induced hepatic lipid deposition and TG content in the HFD + WC group, which was further reduced in the HFD + OC group. Western blot analysis demonstrated inconsistent changes of fatty acid synthesis-related proteins but significantly improved ACOX-1 and CPT-II, indicating that orange carrot carotenoids had the potential to inhibit NAFLD by improving β-oxidation. Further investigation showed significantly higher mRNA and protein levels of PPARα and its transcription factor activity”
“We found that dietary WBM intake significantly lowered liver weight and hepatic injury markers in OVX mice. Pathological examination of liver tissue showed less fat accumulation in the livers of mice on WBM diet; moreover, these animals had improved glucose clearance ability.”
Bamboo shoot dietary fiber alleviates gut microbiota dysbiosis and modulates liver fatty acid metabolism in mice with high-fat diet-induced obesity - PubMed
Our study suggests that BSDF as a prebiotic supplement has the potential to improve obesity by improving gut microbiota and modulating host PPAR and fatty acid metabolic pathways.
pubmed.ncbi.nlm.nih.gov
“We found that BSDF(bamboo shoot dietary fiber) was effective in reducing lipid accumulation in liver and adipose tissue and alleviating dyslipidemia and insulin resistance. Liver transcriptome analysis results showed that BSDF could improve lipid metabolism and liver injury by modulating peroxisome proliferator-activated receptor (PPAR) and fatty acid metabolic pathways.”