Two fasting days a week moved blood pressure and lipids

The 5:2 pattern — two very low-calorie days a week and five normal ones — is one of the most widely tried fasting approaches, largely on the promise of weight loss. Whether it also shifts the markers that actually track cardiovascular risk, such as blood pressure, blood lipids, adipokines and inflammation, is a separate question. It also matters whether people living with type 2 diabetes respond differently from those without it, since they carry higher baseline risk. And because most diet studies stop at the end of the intervention, the durability of any change is rarely tested.

This was a secondary analysis of a non-randomised controlled six-month trial in overweight or obese adults. Ninety-seven individuals were recruited, 35 with type 2 diabetes and 62 without, and 93 completed six months of the 5:2 diet: two fasting days of 500 kilocalories for women and 600 for men, with five days of their usual eating. A total of 82 participants, 31 with type 2 diabetes and 51 controls, returned for a 12-month follow-up. Measurements covered blood pressure, blood lipids, adipokines including adiponectin and leptin, inflammatory markers such as high-sensitivity C-reactive protein, waist circumference and the liver enzyme ALT.

Both groups lost weight over six months: -6.3% in the type 2 diabetes group and -5.0% among controls. Waist circumference, blood pressure, HDL cholesterol, LDL cholesterol and adiponectin all improved significantly. Participants with type 2 diabetes additionally showed falls in ALT and high-sensitivity C-reactive protein that differed significantly from the control group, while controls saw significant reductions in triglycerides and leptin. At 12 months, HDL cholesterol and adiponectin improvements persisted in both groups; the diabetes group also had lower hsCRP and leptin, and the control group a lower ALT.

The findings add cardiovascular risk-factor detail to a fasting pattern usually judged on the scales alone, and they hint that people with type 2 diabetes may gain somewhat greater metabolic benefit. But the trial was not randomised and had no group eating a conventional continuous-deficit diet, so it cannot say whether the 5:2 structure beats simply eating less overall. Attrition between the six- and twelve-month assessments also thins the follow-up sample. Whether these marker changes translate into fewer cardiovascular events is untested here.

This is a reason to think that a 5:2 pattern people can stick with for six months is associated with meaningful shifts in the standard risk panel, not just body weight. It also suggests some of those shifts — particularly HDL cholesterol and adiponectin — may still be detectable a year from the start. What it cannot tell you is whether the fasting schedule is doing anything special, because the same weight loss achieved another way might produce similar results. Treat it as encouraging evidence about one approach rather than proof of its superiority.