Revisiting the concepts of de novo lipogenesis to understand the conversion of carbohydrates into fats: Stop overvaluing and extrapolating the renowned phrase “fat burns in the flame of carbohydrate”

• Published in: Nutrition (Burbank, Los Angeles County, Calif.) Los Angeles County, Calif.), 2025-02, Vol.130, p.112617, Article 112617
• Main Authors: Santos, Heitor O., Penha-Silva, Nilson
• Format: Article
• Language: English
• Subjects: Adipocytes; Adipose tissue; Adipose Tissue - metabolism; Bioaccumulation; Body fat; Burns; Carbohydrate metabolism; Carbohydrates; Cholesterol; de novo lipogenesis; Diet; Dietary Carbohydrates - administration & dosage; Dietary Carbohydrates - metabolism; Dietary Fats; Enzymes; Esterification; Fat mass; Fat metabolism; Fatty acids; Fatty Acids - metabolism; Fatty liver; Fructose; Gastrointestinal surgery; Glucose; Glycerol; High-carbohydrate diet; Humans; Insulin resistance; Lipogenesis; Liver; Liver - metabolism; Liver diseases; Low density lipoprotein; Metabolic disorders; Metabolic syndrome; Molecular structure; Monosaccharides; Non-alcoholic Fatty Liver Disease - etiology; Non-alcoholic Fatty Liver Disease - metabolism; Nutrition research; Obesity; Obesity - metabolism; Oils & fats; Oxidation; Physiology; Sucrose; Weight control
• ISSN: 0899-9007; 1873-1244; 1873-1244
• DOI: 10.1016/j.nut.2024.112617

[Display omitted] •“Fat burns in the flame of carbohydrate” is a praiseworthy phrase, but it appears to be overvalued and extrapolated even nowadays.•De novo lipogenesis cannot be neglected and must be considered an efficient biochemical process in health and disease.•Although the de novo lipogenesis from carbohydrates occurs primarily in the liver, it also occurs in the adipose tissue.•The de novo lipogenesis in adipocytes can attenuate this pathway in hepatocytes and help to prevent hepatic steatosis.•In the liver, the monosaccharides fructose and glucose from saccharose can exacerbate synergistically the de novo lipogenesis. Carbohydrates can be converted into fatty acids via de novo lipogenesis (DNL). Although DNL is considered inefficient, these endogenous fatty acids contribute substantially to the esterification pathway in adipose tissue, together with fatty acids of feeding. This article revisited the concepts of DNL and aimed to discuss the clinical magnitude of carbohydrate overfeeding and fat mass accumulation. Although fat storage resulting from fat intake is more favorable for fat mass accrual than carbohydrates due to molecule structure and metabolism (e.g., oxidation and thermic effect), carbohydrates can substantially participate in lipogenesis and esterification under excess carbohydrate intake over time. Regarding only monosaccharide overfeeding, glucose and fructose favor the subcutaneous and visceral adipose tissue, respectively. While fructose and sucrose are considered villains in nonalcoholic fatty liver disease, energy surplus from carbohydrates, regardless of sources, can be considered an underlying cause of obesity. Interestingly, some degree of DNL in adipocytes may be favorable to mitigate a high deposition of fatty acids in the liver, conferring a physiological role. Although "fat burns in the flame of carbohydrate" is a praiseworthy phrase that has helped describe basic concepts in biochemistry for many decades, it appears to be overvalued and extrapolated even nowadays. DNL cannot be neglected. It is time to consider DNL an efficient biochemical process in health and disease.