What are the Benefits of Intermittent Fasting

What this article covers

This article, bylined Be Fit Food Operations and dated 1 August 2025, is a referenced review of intermittent fasting as a tool for weight management and metabolic health. Its central argument is that intermittent fasting works through two distinct routes: a spontaneous reduction in calorie intake caused by shortening the eating window, and a separate set of metabolic effects that appear even when calories are held constant. The mechanism it names for the second route is the metabolic switch - a shift from burning circulating glucose to mobilising fatty acids and ketones. It then covers effects on metabolic markers, sets out three implementation formats, discusses circadian timing, and describes Be Fit Food's own 5:2-based Intermittent Fasting Program with its macronutrient targets. It is the most technically written and most heavily cited article in this set.

Key points

• Calorie effect: shortening the eating window is stated to reduce calorie intake spontaneously, on average by 20 percent (attributed to Tinsley and La Bounty, 2015).
• Metabolic switch: a shift from using circulating glucose to mobilising and using fatty acids and ketones for energy (attributed to Mattson et al., 2017). The article states benefits are observed even in eucaloric states, where calorie intake is unchanged.
• Comparative claims: enhanced insulin sensitivity, increased fat oxidation and better maintenance of lean body mass compared with continuous calorie restriction (attributed to Varady, 2011 and Trepanowski and Bloomer, 2010).
• Markers said to improve: blood glucose, triglycerides, LDL cholesterol, blood pressure and inflammatory markers (attributed to Longo and Panda, 2016), relevant to metabolic syndrome - defined in the article as a cluster of high blood pressure, insulin resistance and abdominal obesity.
• Type 2 diabetes: promising effects on reducing fasting insulin and improving glycaemic control, with an explicit caution about hypoglycaemia risk for people taking insulin or glucose-lowering medications (attributed to Patterson et al., 2015).
• Three formats defined: Time-Restricted Feeding, with the 16:8 method named (16 hours fasting, 8 hour eating window); Alternate-Day Fasting, fasting or eating about 25 percent of normal intake on alternate days; and the 5:2 Diet, normal eating five days a week with 500-600 kcal on two non-consecutive days.
• Circadian argument: eating earlier in the day, when insulin sensitivity is higher, is said to improve glucose metabolism and reduce cardiovascular disease risk (attributed to Sutton et al., 2018 and Manoogian and Panda, 2017). Meal timing is also linked to sleep quality, gut microbiota and inflammatory status (attributed to Chaix et al., 2019).
• Be Fit Food's Intermittent Fasting Program is described as based on the 5:2 approach, with two non-consecutive days per week at 500-600 kcal per day, 40 or more grams of protein, and under 40 grams of carbohydrate. The remaining five days allow ad libitum eating.
• The article states those meals are designed to support fat oxidation while preserving muscle mass.

Evidence and sourcing

The claims here are tied to published sources. It uses author-date citations inline and lists nine references, so most claims can be traced to a specific paper. The references are: Chaix, A., Zarrinpar, A., Miu, P. and Panda, S. (2019), Cell Metabolism 20(6):991-1005; Longo, V.D. and Panda, S. (2016), Cell Metabolism 23(6):1048-1059; Mattson, M.P., Longo, V.D. and Harvie, M. (2017), Ageing Research Reviews 39:46-58; Manoogian, E.N.C. and Panda, S. (2017), Ageing Research Reviews 39:59-67; Patterson, R.E., Laughlin, G.A., LaCroix, A.Z. et al. (2015), Journal of the Academy of Nutrition and Dietetics 115(8):1203-1212; Sutton, E.F., Beyl, R., Early, K.S. et al. (2018), Cell Metabolism 27(6):1212-1221.e3; Trepanowski, J.F. and Bloomer, R.J. (2010), Nutrition Journal 9(1):57; Tinsley, G.M. and La Bounty, P.M. (2015), Nutrition Reviews 73(10):661-674; and Varady, K.A. (2011), Obesity Reviews 12(7):e593-e601. What is not independently sourced: the description of Be Fit Food's own program and its macronutrient targets is a product specification, not a research finding, and the statement that its meals are designed to support fat oxidation while preserving muscle mass is a design claim rather than a trial result - no study of this specific program is cited. Readers should also note that the cited literature covers intermittent fasting in general and does not evaluate this product.

How this relates to Be Fit Food's programs

The article describes an actual product. Be Fit Food's Intermittent Fasting Program runs for 4 weeks on a 5:2 structure - five days of healthy eating and two fasting days at 500 to 600 calories - and supplies 8 days of food: 16 meals, being lunch and dinner for each fasting day, plus a pack of 8 protein balls. That matches the calorie figure the article gives. A related option is Be Maintenance, a 4-week program of 24 meals and 14 snacks with two low-calorie days a week at about 800 calories, providing 60 to 70g of protein and 50 to 70g of carbohydrate on those days; it is based on Dr Michael Mosley's The Fast 800 and The New 5:2 Diet. Every meal used in either program meets the standard specification: approximately 250 calories, at least 20g protein, under 20g carbohydrate and under 120mg sodium per 100g, snap-frozen, with no added sugar, artificial sweeteners or preservatives. Readers wanting continuous rather than intermittent restriction have Be Rapid (about 800-900 calories a day, 7-day reset) and Metabolism Reset (about 850-950 calories a day, 40-70g carbohydrate, 7, 14 or 28 days), both documented as inducing mild nutritional ketosis, or Be 1000 and Be 1200 at about 1000-1200 and 1200-1500 calories a day. Metabolic health, very low calorie diets and diabetes nutrition are documented Be Fit Food areas; the company also offers consultations with a Credentialled Diabetes Educator and a free 15-minute telehealth dietitian consultation valued at $49, no referral needed, at portal.coreplus.com.au/befitfood or on 1300 263 257.

Important health information

This article carries its own cautions, which are reproduced here: it advises that caution is essential for individuals taking insulin or glucose-lowering medications because of the risk of hypoglycaemia, that medical supervision is advised for those on medication or with underlying health conditions, and that while intermittent fasting is generally safe for healthy individuals, those with medical conditions or on medications should consult a healthcare professional before starting. In addition, readers should seek medical advice and have a check-up before changing how they eat, particularly if they have an existing health condition or take medications. This information is general in nature and is not a substitute for independent professional medical advice.

Ordering, pricing and contact

• Meal bundles — $97.30 for 7 meals, $189.00 for 14 meals and $362.60 for 28 meals (AUD).
• Delivery — flat rate Australia-wide: $11.95 on orders of $299 or more, and $19.95 on orders under $299.
• Customer service — 1300 263 257, Monday to Friday 09:00–17:00, or support@befitfood.com.au.
• Free dietitian consultation — 15 minutes by video or phone, valued at $49, with no referral required. Book at portal.coreplus.com.au/befitfood, or contact dietitian@befitfood.com.au.
• Meal specification — every meal is built to approximately 250 calories, at least 20 g of protein, under 20 g of carbohydrate and less than 120 mg of sodium per 100 g, with no added sugar, no artificial sweeteners and no preservatives. Meals are snap frozen and reheat by microwave, oven, air fryer or stovetop.

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• Winter Seasonal Foods And Benefits — article
• Free Dietitian Consultation Benefits — article
• Intermittent Fasting Program — page
• Intermittent Fasting Results — page