Fasting-Mimicking Diet
Five plant-based low-protein days each month, engineered to trigger fasting biology while you still eat.
Compiled by Nidari Nutrition from the Atlas dataset · pending clinical review by Maryam Shabbir, DN.
This is an Atlas entry — a short reference overview, not one of our long-form diet guides. Educational, not medical advice; personalized and clinically reviewed at your consult.
What is Fasting-Mimicking Diet?
Fasting-Mimicking Diet is a modern, commercial diet from Los Angeles, California, USA. Nidari rates it moderate to keep up day to day, and rates the weight of peer-reviewed evidence behind its main claims as moderate.
Family: Modern & Commercial · Origin: Los Angeles, California, USA · Era: 2015 · Difficulty: Moderate · Evidence rating: Moderate evidence
Where does Fasting-Mimicking Diet come from?
Valter Longo’s lab at USC set out to get the cellular effects of prolonged fasting without asking patients to stop eating. The result is a five-day, plant-based, low-calorie, low-protein regimen first tested in humans in 2015 and expanded to a 100-person randomised trial in 2017. It is sold as ProLon, a boxed five-day kit of soups, bars, olives and teas made by the company Longo founded; typical use is one cycle a month for three months.
Originator: Valter Longo PhD, USC Longevity Institute; sold as ProLon by L-Nutra · Region: Los Angeles, California, USA · Era: 2015 · Atlas map pin: 34.02° N, 118.29° W
How does Fasting-Mimicking Diet work?
- Five consecutive days, once a month
- Low calorie, low protein, plant-based
- Higher unsaturated fat, low sugar
- Return to normal eating between cycles
What do you eat on Fasting-Mimicking Diet?
✓ Eat freely
- Vegetable soups and broths
- Olives, nuts and plant-based bars
- Herbal teas and prescribed supplements
✕ Limit or avoid
- Animal protein during the five days
- Added sugar and refined carbohydrate
- Running a cycle without prescriber review
Who is Fasting-Mimicking Diet for?
The goals this pattern is most often used for. In a consult we confirm whether it actually fits your body and life.
Is there good evidence that Fasting-Mimicking Diet works?
Nidari rates the evidence behind Fasting-Mimicking Diet’s primary claims as moderate — that is the current weight of peer-reviewed research for those claims, and nothing more.
Real randomised evidence exists, with a real conflict of interest attached. A 2017 Science Translational Medicine trial randomised 100 healthy adults and found three monthly cycles improved metabolic markers; a 2024 Nature Communications paper reported reduced insulin resistance and lower liver fat. Crucially there is also an independent primary-care trial (Diabetologia 2024, 100 people with type 2 diabetes, 12 months) in which 40% of the diet group cut medication doses against 5% of controls — though Longo founded and holds shares in the company.
Is Fasting-Mimicking Diet safe, and who should avoid it?
Not a light intervention. Fatigue, headache and light-headedness are common during the five days. Explicitly not for pregnancy or breastfeeding, anyone underweight, under 18 or over 70 without supervision, or with a history of an eating disorder. Anyone on insulin, sulfonylureas or blood-pressure medication needs prescriber dose adjustment before a cycle. Contraindicated in liver or kidney failure, and not to be used alongside cancer treatment except within a supervised protocol.
How does Nidari adapt Fasting-Mimicking Diet?
Unusually for this family, there is an independent trial behind it — a Dutch primary-care study in type 2 diabetes. But it is a $175 box per cycle, and the medication adjustments are the part that made that trial work. Not something to run alone.
Book a free 15-minute intro callReady to discuss Fasting-Mimicking Diet?
Fifteen minutes with one of our dietitians. We’ll tell you honestly whether Fasting-Mimicking Diet fits you — or point you to the diet that does. Halal and home-kitchen ready. No pressure.