Key Takeaways
1. Intermittent fasting and rapid weight loss can reverse type 2 diabetes
"Type 2 diabetes (the sort of diabetes you get when you are older) can be put into remission, perhaps even 'cured', by a rapid weight loss diet."
Groundbreaking research: Professor Roy Taylor of Newcastle University conducted studies showing that losing over 10% of body weight can drain fat from the liver and pancreas, restoring the body to its former health. The DIRECT (DIabetes REmission Clinical Trial) study, involving 298 patients, demonstrated that an 800-calorie-a-day rapid weight loss diet led to:
- An average weight loss of 10kg compared to 1kg in the control group
- Nearly half of the participants bringing their blood sugars back to normal without medication
- 86% of those who lost more than 15kg went into remission
Implications: This research challenges the long-held belief that type 2 diabetes is incurable and can only be managed with medication. It offers hope to millions of people affected by this condition and suggests that dietary interventions can be more effective than traditional treatments.
2. The Fast 800 approach combines rapid weight loss and intermittent fasting
"The Fast 800 still incorporates the 5:2, but is based on, among other things, more manageable 800-calorie fast days."
Three stages: The Fast 800 program consists of:
- Very Fast 800: 800 calories daily for 2-12 weeks
- New 5:2: 800 calories for 2 days a week, Mediterranean diet for 5 days
- Maintenance: Healthy Mediterranean-style eating with optional weekly fast day
Flexibility and sustainability: This approach allows for personalization based on individual goals and preferences. The gradual transition from rapid weight loss to a more sustainable eating pattern helps maintain results long-term. The 800-calorie threshold is high enough to be manageable but low enough to trigger desirable metabolic changes.
3. Ketosis is key to fat burning and appetite suppression
"Ketones, as I mentioned earlier, are produced by your liver when you 'flip the metabolic switch', and your body goes from burning sugar to burning fat for fuel."
Benefits of ketosis:
- Enhanced fat burning
- Reduced appetite
- Improved mental clarity
- Potential neuroprotective effects
Achieving ketosis: The Fast 800 approach induces mild ketosis through:
- Low-carb, high-protein Mediterranean-style diet
- Intermittent fasting
- Time Restricted Eating
By maintaining ketosis, especially during fasting periods, the body becomes more efficient at using fat for fuel, leading to more effective weight loss and metabolic improvements.
4. A low-carb Mediterranean diet optimizes health and weight loss
"The reason I am such a fan of the Mediterranean diet is not just because it tastes great but because there is so much solid scientific evidence that adopting this lifestyle will cut your risk of heart disease, cancer, type 2 diabetes, depression and dementia."
Key components:
- Abundant vegetables and fruits
- Healthy fats from olive oil, nuts, and fish
- Moderate protein from lean meats and legumes
- Limited refined carbohydrates and sugars
Scientific support: The PREDIMED study, involving over 7,400 participants, found that those following a Mediterranean diet had:
- 30% reduced risk of heart attack or stroke
- 58% reduced risk of type 2 diabetes
- 51% reduced risk of breast cancer
- Reduced risk of cognitive decline
This dietary approach not only supports weight loss but also promotes overall health and longevity, making it an ideal foundation for the Fast 800 program.
5. Time Restricted Eating (TRE) enhances intermittent fasting benefits
"TRE is not an alternative to the 5:2; rather, it complements it."
How TRE works:
- Eat all calories within a defined window (e.g., 8-12 hours)
- Extends overnight fasting period
- Allows body to burn fat and perform essential repairs
Research findings:
- Improved metabolic health
- Enhanced weight loss
- Better sleep quality
- Potential reduction in cancer risk
Combining TRE with the Fast 800 approach can amplify the benefits of intermittent fasting, leading to more pronounced improvements in weight loss and overall health. Starting with a 12-hour eating window and gradually reducing it to 8-10 hours can make the transition easier and more sustainable.
6. Exercise and stress management are crucial for long-term success
"Being active is a great way of distracting yourself and will boost your mood."
Exercise benefits:
- Preserves muscle mass during weight loss
- Improves insulin sensitivity
- Enhances mood and reduces stress
- Supports long-term weight maintenance
Stress management techniques:
- Mindfulness meditation
- Regular physical activity
- Adequate sleep (7-8 hours per night)
- Social connections and support
Incorporating both exercise and stress management into the Fast 800 program helps address the psychological aspects of weight loss and promotes overall well-being. This holistic approach increases the likelihood of long-term success and sustainable lifestyle changes.
7. Meal planning and preparation are essential for adhering to the Fast 800
"Having no food in the house is almost as bad as having lots of junk food. You will end up eating takeaways or dropping into the petrol station to buy snacks."
Meal planning strategies:
- Clear out unhealthy foods from your home
- Stock up on nutritious, low-carb ingredients
- Prepare meals in advance
- Keep healthy snacks on hand for emergencies
Key foods to include:
- Vegetables (especially leafy greens)
- Healthy fats (olive oil, avocado, nuts)
- Lean proteins (fish, poultry, legumes)
- Limited fruits (berries, apples)
By planning and preparing meals in advance, you reduce the likelihood of impulsive eating and ensure that you always have Fast 800-compliant options available. This proactive approach significantly increases adherence to the program and supports long-term success.
8. Mindfulness and behavioral changes support sustainable weight loss
"Willpower is hugely overrated and relying on it is one of the main reasons why so many diets fail."
Mindfulness techniques:
- Mindful eating practices
- Regular meditation
- Stress-reduction exercises
- Self-awareness of eating triggers
Behavioral strategies:
- Set clear, achievable goals
- Track progress (weight, measurements, blood tests)
- Develop new habits to replace old ones
- Build a support network
Incorporating mindfulness and behavioral changes into the Fast 800 program addresses the psychological aspects of weight loss and helps create lasting lifestyle changes. These practices support long-term success by reducing reliance on willpower alone and fostering a more balanced, sustainable approach to eating and health.
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Review Summary
The Fast 800 receives mostly positive reviews, with readers praising its clear explanations of intermittent fasting and the Mediterranean diet. Many found success with the 800-calorie plan and time-restricted eating. Reviewers appreciate Mosley's personable approach and scientific backing. Some criticize the changing advice from previous books and the potential difficulty of maintaining the diet long-term. Overall, readers find the book informative, motivating, and practical for weight loss and health improvement.