The Science
The Fast 800 lifestyle is designed based on the latest in diet and health research
800 Calories and Rapid Weight Loss
The DiRECT Trial
Background: A major study that explored the power of an 800 calorie/day for 3-5 months diet to achieve major weight loss and remission from type 2 diabetes.
Results: A staggering 46% of participants in the intervention (800 cal) group achieved remission from diabetes, compared to only 4% in the control group. Weight loss statistics were equally impressive, after 12 months 24% of the 800 group had still lost more than 15kg of weight, compared to 0% in the control group. Not only did they lose more weight, but also kept more of it off.
Find out more: Lean, M., Leslie, W., Barnes, A., et al. (2018). Primary care-led weight management for the remission of type 2 diabetes (DiRECT): an open-label, cluster-randomised trial. Lancet, 391(10120), pp. 541-551. View study
The DROPLET Trial
Background: Obese and overweight participants were assigned to either an 800 calorie/day diet for 8 weeks, or a control group who were given the current usual care support. The 800 cal diet was coupled with behavioural support and a structured food reintroduction.
Results: The intervention (800 cal) group lost over three time more weight than the control group, losing an average of 10.7kg 12 months after starting the programme. 45% of participants in the 800 cal group lost more than 10% of their initial body weight. The intervention group also showed more improvements in various other health markers than the control group.
Find out more: Astbury, N., Aveyard, P., Nickless, A., Hood, K., Corfield, K., Lowe, R., Jebb, S. (2018) Doctor Referral of Overweight People to Low Energy total diet replacement Treatment (DROPLET): pragmatic randomised controlled trial. BMJ, 362:k3760. View study
The PREVIEW Study
Background: The PREVIEW lifestyle intervention study is, to date, the largest, multinational study aimed at preventing type 2 diabetes. 2,326 pre-diabetic patients from eight countries followed an 800-calorie diet for eight weeks as part of a longer term weight loss management and diabetes prevention study.
Results: After eight weeks, participants had lost an average of 11kg, and experienced an average reduction of 10cm in waist size.
Find out more: Christensen, P, Meinert Larsen, T, et al. (2018), ‘Men and women respond differently to rapid weight loss: Metabolic outcomes of a multi-centre intervention study after a low‐energy diet in 2500 overweight, individuals with pre-diabetes (PREVIEW)’ Diabetes Obes Metab. 2018; 20: 2840– 2851. doi: doi.org/10.1111/dom.13466. View study
Intermittent Fasting
Fasting-Mimicking Diet (FMD)
Background: Another major study, this time looking at the effect on various health markers of a very low calorie diet (700-1000 kcal/day) for 5 days every month for 3 months.
Results: The three cycles of FMD reduced body weight, trunk and total body fat, blood pressure and IGF-1 in comparison to a normal diet. These results were especially pronounced in the most ‘at risk’ portions of the trial groups.
Find out more: Wei, M., Brandhorst, S., Shelehchi, M., et al. (2017). Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer and cardiovascular disease. Sci Transl Med, 9(377). View study
Intermittent Fasting vs Conventional Dieting
Background: This study compared the effects of 3 months of Intermittent Energy and Carbohydrate Restriction (IECR) compared to conventional Daily Energy Restriction (DER). The IECR group followed a 5:2 plan with 600-650 kcal/day on fasting days.
Results: The participants on the IECR diets had lost, on average, twice as much body fat as those on the DER diet. Participants on the IECR diets also had significantly greater reductions in insulin resistance than those on the DER diet.
Find out more: Harvie, M., Wright, C., Pegington, M., et al. (2013). The effect of intermittent energy and carbohydrate restriction v. daily energy restriction on weight loss and metabolic disease risk markers in overweight women. British Journal of Nutrition, 110(8), pp. 1534-1547. View study
Intermittent Fasting and Asthma in Overweight Subjects
Background: This study examined the effects of alternate day calorie restriction (ADCR) on various health markers for overweight patients (BMI >30) with asthma. Participants spent 8 weeks eating normally every other day and eating 20% of their usual calorie consumption on the intervening days.
Results: Participants who stuck to the diet lost 8% of their initial body weight on average during the 8 weeks. Subjects’ asthma-related symptoms, control, peak expiratory flow (PEF) and quality of life (QoL) significantly improved. Results showed that an ADCR diet can have rapid and sustained beneficial effects.
Find out more: Johnson, J. B., W. Summer, R. G. Cutler, B. Martin, D. H. Hyun, V. D. Dixit, M. Pearson, M. Nassar, S. Maudsley, O. Carlson, S. John, D. R. Laub and M. P. Mattson (2007) Alternate day calorie restriction improves clinical findings and reduces markers of oxidative stress and inflammation in overweight adults with moderate asthma. Free Radic Biol Med, 42(5), pp. 665-674. View study
Mediterranean Diet
The PREDIMED Trial
Background: This was a very large trial involving 7447 individuals, who were at high risk of cardiovascular disease. Participants were randomised to a med diet supplemented with either nuts or extra virgin olive oil, or to a low-fat control group. The effects of the diet after more than 5 years observation were then investigated.
Results: A large number of papers have been published on this trial, and so the key results from each will be summarised very briefly here.
- A mediterranean diet was shown to reduce the risk of a major cardiac event by 30% in the trial cohort.
- The med + nuts diet was associated with a 13.7% reduction in prevalence of metabolic syndrome.
- Oxidised cholesterol levels, along with several other heart disease risk factors, reduced significantly in the groups on the mediterranean diet.
- The mediterranean diet reduced the risk of developing type 2 diabetes by 52%.
- The mediterranean diet had beneficial effects on various cardiovascular risk factors including blood sugar levels and blood pressure.
Find out more:
- Estruch, R., Ros, E., Salas-Salvadó, J., et al. (2013) Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. N Eng J Med, 378, e34. View study
- Salas-Salvadó, J., Fernández-Ballart, J., Ros, E., et al (2008) Effect of a Mediterranean Diet Supplemented With Nuts on Metabolic Syndrome Status: One-Year Results of the PREDIMED Randomized Trial. Arch Intern Med, 168(22), pp. 2449-2458. View study
- Fitó, M., Guxens, M., Corella, D., et al. (2007) Effect of a traditional Mediterranean diet on lipoprotein oxidation: a randomized controlled trial. Arch Intern Med, 167(11), pp. 1195-1203. View study
- Sala-Slavadó, J., Bulló, M., Martínez-González, MÁ (2011) Reduction in the incidence of type 2 diabetes with the Mediterranean diet: results of the PREDIMED-Reus nutrition intervention randomized trial. Diabetes Care, 34(1), pp. 14-19. View study
- Estruch, R., Martínez-González, MÁ., Corella, D., et al (2006) Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomized trial. Ann Intern Med, 145(1), pp. 1-11. View study
Adherence to Mediterranean diet and health status: meta-analysis
Background: This meta-analysis, conducted in 2008 by the University of Florence, reviewed the findings of 12 studies, together following 1.5m people.
Results: It found that those following a Mediterranean diet were 9% less likely to die young, and also less likely overall to die of heart disease, stroke or cancer. They were also less likely to develop Parkinson’s disease or Alzheimer’s.
Find out more: Sofi F., Cesari F., et al. (2008), ‘Adherence to Mediterranean diet and health status: meta-analysis’ BMJ 2008; 337:a1344, doi https://doi.org/10.1136/bmj.a1344. View study