Obesity and cancer co-diseases are most likely linked by inflammation and oxidative stress. A recent study evaluated whether the nutritional ketosis and weight loss induced by a very-low-calorie ketogenic diet (VLCKD) modulate the inflammatory and oxidative stress profile, compared with a standard, balanced hypocaloric diet (LCD) or bariatric surgery (BS) in patients with obesity.

The study included 79 patients with overweight or obesity and 32 normal-weight volunteers as the control group. Patients with obesity experienced weight reduction therapy based on VLCKD, LCD, or BS. The study quantified the circulating levels of a multiplexing test of cytokines and carcinogenesis/aging biomarkers, along with lipid peroxides and total antioxidant power.

The study observed-

• An increase in pro-inflammatory cytokines, while a decrease in anti-inflammatory cytokines under excessive body weight.
• When patients underwent weight loss strategies, there were energy-restricted and surgical strategies of weight loss-induced changes in circulating cytokine and lipid peroxides.
• This effect was more prominent in patients following the VLCKD than the LCD or BS, and it appeared mainly in the ketosis phase of the intervention.
• IL-11, IL-12, IL-2, INF-γ, INF-β, Pentraxin-3 or MMP1 changed particularly after VLCKD.
• While APRIL (a proliferation-inducing ligand), TWEAK (TNF-like weak inducer of apoptosis), osteocalcin, and IL-28A were raised after BS.

This is the pioneer study to evaluate the time course of cytokines and oxidative stress markers after a VLCKD as compared with a standard LCD and BS. The results of this study support the immunomodulatory effect of nutritional ketosis induced by a VLCKD synergistically with a weight loss strategy to improve innate immunity and prevent infections and carcinogenesis in patients with obesity.

Clinical Nutrition. 2022;41(7):1566-1577. DOI:https://doi.org/10.1016/j.clnu.2022.05.007