Weight loss to blood pressure: CMC Vellore doctor decodes direct and indirect benefits of intermittent fasting

Skipping meals isn’t just a fad anymore—intermittent fasting (IF) has gone from buzzword to lifestyle for millions. But what does science really say about it? Dr Sudhir Kumar, a CMC Vellore–trained neurologist, decided to break it down on X, cutting through the hype with a no-nonsense summary. His take: yes, fasting works, but not always for the reasons people think. And it definitely comes with caveats.

When it comes to blood pressure, the doctor says results are modest at best. Some studies show a small dip in systolic and diastolic numbers, but most of the improvement is linked to weight loss, not fasting alone. Cholesterol, however, fares better—many people see a drop in total and LDL cholesterol, especially if they’re overweight or obese.

Effects on brain
The brain angle is where things get really interesting. Animal studies suggest fasting boosts brain-derived neurotrophic factor (BDNF), which supports neuroplasticity, learning, and memory. Early human research hints at similar effects, but the evidence isn’t strong enough yet to call it a proven brain hack.

✅Intermittent fasting (IF): What the evidence actually shows (quick summary)

1. Blood pressure: Modest, inconsistent reductions.
Some trials report small falls in systolic/diastolic BP, especially when fasting causes weight loss.
2. Cholesterol / non-HDL cholesterol: Often…

— Dr Sudhir Kumar MD DM (@hyderabaddoctor) September 19, 2025

Gut health

Fasting does shake things up, with noticeable changes in the microbiome, but the patterns are all over the place. There’s no single “healthy” fasting microbiome that fits everyone. What does seem consistent, though, is reduced inflammation. Many studies show a fall in markers like CRP, again tied partly to losing weight.

Bonus benefits
Improved insulin sensitivity, better glucose control, smaller waistlines, and of course, weight loss. But Dr. Kumar reminds people that fasting isn’t for everyone. Pregnant or breastfeeding women, those with eating disorders, unstable diabetes, or frail elderly adults should stay away unless guided by a doctor.

The real kicker? Most of the benefits aren’t because of some magical fasting window—they come from eating fewer calories overall. Whether you’re doing time-restricted eating, alternate-day fasting, or the 5:2 plan, results differ depending on your body, health, and how long you stick with it.