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INTERMITTENT FASTING DIET PLAN FOR WEIGHT LOSS

INTRODUCTION

Periods of voluntary moderation from food and drink (i.e., intermittent fasting) has been practiced since earliest ancient times by peoples around the globe. Books on ethnology and religion describe a remarkable variety of fasting forms and practices. Renewed interest in fasting regimens is evidenced by an excess of popular press publications and diet recommendations (Brongers,1997).

Intermittent Fasting vs Calories Restriction

While entering the discussion about intermittent fasting, it is important to understand the difference between caloric restriction and intermittent fasting. Calorie restriction (CR) is a reduction in total caloric intake that does not result in malnutrition. This has consistently been found to result in decreased body weight and increased longevity in many species, including non-human primates. Among overweight humans, short-term CR (6-months) has been shown to significantly improve multiple cardiovascular risk factors, insulin sensitivity, and mitochondrial function. Likely due to these physiological changes, clinical trials indicate CR may have several beneficial effects among overweight adults, in addition to weight loss. However, over the past several decades, obesity intervention trials have revealed that most individuals experience difficulties sustaining daily CR for extended periods of time.

Types of Intermittent Fasting

More studies are needed to evaluate mechanisms, efficacy in humans, target populations, and safety of intermittent fasting. There are numerous intermittent fasting regimens ranging from 12- to 16-hour daily fasts to 5:2 strategy, and it remains uncertain which strategy is the best for cardiovascular health, especially with evidence suggesting that intermittent fasting regimens should follow circadian rhythms. Some of the most common ways are:

The 16:8 method

16:8 intermittent fasting method is a form of time-restricted fasting. It works by allowing consumption of foods during an 8-hour window and avoiding food or fasting for the remaining 16 hours each day. People who follows the 16:8 method abstain from taking food at night and for part of the morning and evening. During the middle of the day, they tend to consume their daily calories (NA, 2020). This method of intermittent fasting can be repeated as often as you’d like or even done once or twice. Finding the right eating and fasting windows for this method might take a few days to figure out, especially if you’re very active or if you wake up hungry for breakfast.

The 16:8 intermittent fasting table

The 5:2 method

This approach to intermittent fasting focuses on capping your calories at 500 for two days a week. During the other five days of the week, you maintain a healthy and normal diet. On fasting days, this approach usually includes a 200-calorie meal and a 300-calorie meal. It’s important to focus on high-fiber and high-protein foods to help fill you up and keep calories low when fasting (menshealth.com, 2019)

The 5:2 intermittent fasting table

The eat-stop-eat method

It’s a method of intermittent fasting which involves two, non-consecutive, 24 hour fasts per week. That means that two days a week, you’ll eat just one meal. Whether that’s breakfast, lunch, or dinner is up to you, and you can vary it as you wish. An example week might look like this:

Benefit of Intermittent Fasting

Help weight loss                                 

Trepanowski et al., 2017, compared the effects of alternate-day fasting vs. daily calorie restriction on weight loss, weight maintenance, and risk indicators for cardiovascular disease. This was a randomized clinical trial of obese adults (18 to 64 years of age; mean body mass index, 34) at a single-centre academic institution in Chicago. Participating individuals were randomized to one of three groups for one year: alternate-day fasting (25% of energy needs on fast days; 125% of energy needs on alternating “feast days”), calorie restriction (75% of energy needs every day), or a no-intervention control. The primary outcome was a change in body weight.

Secondary outcomes were adherence to the dietary intervention and risk indicators for cardiovascular disease. Over the course of 12 months, the control group maintained their weight around the baseline weight, while the alternate-day fasting and daily caloric restriction groups, by 6 months, both exhibited a lowest point in weight 7% below the baseline weight (not significantly different from each other before exhibiting some later weight gain, ending at 12 months approximately 4.5% below starting weight. There was a 38% dropout in the alternate-day fasting group compared to 29% in the daily calorie restriction group and 26% in the control group. Overall, the authors concluded that alternate-day fasting did not improve health beyond calorie restriction.

Help in blood sugar

There are several proposed mechanisms regarding the development of insulin resistance. One prominent theory relates to associations between increased adiposity and subsequent chronic inflammation, leading to the development of insulin resistance in tissues. Intermittent fasting can decrease adiposity and related insulin resistance through reduced caloric intake and metabolic reprogramming. Another hypothesis is that decreased energy intake, such as that achieved through intermittent fasting, will cause a prolonged decrease in insulin production and increased levels of AMPK, which likely plays a role in the improvements in insulin sensitivity and glucose homeostasis.

CONCLUSION

In summary, intermittent fasting has shown positive effects on weight loss, in addition to reducing insulin resistance and favourably shifting the levels of leptin and adiponectin. Pre-clinical and clinical studies have demonstrated that intermittent fasting has a wide range of benefits for many diseases, including obesity, T2DM, and hypertension, and in improving cardiovascular risk factors. One argument against intermittent fasting is that, despite extensive animal data, many clinical trials have failed to show as significant improvements of intermittent fasting over caloric restriction.

REFERENCES

  1. Brongers HA. Instruction and Interpretation: Studies in Hebrew Language, Palestinian Archaeology and Biblical Exegesis. Belgium: Brill Academic Pub.; 1997.
  2.  Kerndt P.R., Naughton J.L., Driscoll C.E., Loxterkamp D.A. Fasting: The history, pathophysiology and complications. West. J. Med. 1982;137:379–399. 
  3.  Moro T, Tinsley G, Bianco A, et al. Effects of eight weeks of timerestricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. J Transl Med 2016;14:290
  4. Nowosad K., Sujka M. Effect of Various Types of Intermittent Fasting (IF) on Weight Loss and Improvement of Diabetic Parameters in Human. Curr. Nutr. Rep. 2021;10:146–154. doi: 10.1007/s13668-021-00353-5. 
  5. https://www.healthline.com/nutrition/16-8-intermittent-fasting
  6. https://simple.life/blog/eat-stop-eat-plan/
  7. Trepanowski J.F., Kroeger C.M., Barnosky A., Klempel M.C., Bhutani S., Hoddy K.K., Gabel K., Freels S., Rigdon J., Rood J., et al. Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardioprotection Among Metabolically Healthy Obese Adults: A Randomized Clinical Trial. JAMA Intern. Med. 2017;177:930–938. doi: 10.1001/jamainternmed.2017.0936
  8. Albosta M., Bakke J. Intermittent fasting: Is there a role in the treatment of diabetes? A review of the literature and guide for primary care physicians. Clin. Diabetes Endocrinol. 2021;7:3. doi: 10.1186/s40842-020-00116-
  9. NA (2020), A Guide To 16:8 Intermittent Fasting. https://www.medicalnewstoday.com/articles/324882#summary