In June 2024, 53‑year‑old Lorraine Kerr, a local‑government employee from the UK, returned from a holiday on the Greek island of Symi feeling unable to walk due to menopause‑related fatigue and weight‑related discomfort.. after hearing of Dr Michael Mosley’s death on the same island, she enrolled in his Fast 800 diet and, within a year, dropped to eight stone, eliminated IBS, stabilized borderline diabetes and saw her hot flushes disappear.

From 14 st 7 lb to eight stone: the 12‑week Very Fast 800 sprint

The Fast 800 app guided Kerr through a “Very Fast 800” phase that limited her intake to 800‑900 calories across two to three Mediterranean‑style meals per day for twelve weeks. She paired the plan with daily resistance and HIIT workouts, as the app recommended. According to the source, she lost a full stone during this period.

After the initial phase, Kerr transitioned to the “New 5:2” schedule, eating 800 calories on two non‑consecutive days and eating sensibly the rest of the week. by summer 2025 she reached her target weight of eight stone and a size 8.

Health turn‑arounds: IBS, blood sugar and menopausal flushes

Kerr reports that IBS symptoms vanished within three days of starting the diet, and reappeared only when she re‑introduced artificial sweeteners, suggesting a strong dietary trigger. She also notes that her erratic blood‑sugar levels, which had placed her on the brink of diabetes, normalized within a year of following the programme.

Menopausal hot flushes, which had plagued her for several years, subsided after a few months on the low‑calorie Mediterranean plan, according to the account.

Why the Fast 800 resonated: Mediterranean meals and tech‑enabled support

The Fast 800 app generated daily recipes and shopping lists, helping Kerr move from a lifelong aversion to vegetables to regular consumption of broccoli, kale and chickpeas. Her typical day now includes Greek yoghurt with fruit for breakfast, chickpea curry or broccoli soup for lunch, and herb‑crusted fish or beef hotpot for dinner.

Beyond food, the app’s structured exercise videos kept her accountable, allowing her to progress from beginner to advanced levels, eventually adding yoga and sea‑swim sessions five mornings a week.

Who remains silent? Gaps in the evidence behind the Fast 800

While Kerr’s story highlights dramatic personal results, the source does not provide independent clinical data confirming the diet’s long‑term safety or its efficacy across broader populations. It also omits any input from medical professionals who might have monitored her blood‑sugar or hormonal changes.

Furthermore, the report does not disclose whether Kerr’s weight loss was sustained beyond the first year, leaving the durability of the transformation unclear.

What readers can take away: goal‑setting over scale‑watching

Kerr emphasizes that focusing on life‑changing goals rather than the numbers on the scale helped her avoid post‑diet relapse. After hitting eight stone, she redirected her energy into fine‑art photography and local‑government projects, creating a new purpose that supports lasting health habits.

According to the source, this mindset shift was crucial for maintaining her new weight and preventing emtional eating cycles that had previously driven her weight gain.