Potential Effects of Prolonged Water-Only Fasting Followed by a Whole-Plant-Food Diet on Salty and Sweet Taste Sensitivity and Perceived Intensity, Food Liking, and Dietary Intake

Abstract

The overconsumption of calorie-dense foods high in added salt, sugar, and fat is a major contributor to current rates of obesity, and methods to reduce consumption are needed. Prolonged water-only fasting followed by an exclusively whole-plant-food diet free of added salt, oil, and sugar may reduce the consumption of these hyper-palatable foods, but such effects have not been quantified. Therefore, we conducted a preliminary study to estimate the effects of this intervention on salty and sweet taste detection and recognition thresholds and perceived taste intensity after at least five days of fasting and at refeed day three. We also assessed the effects on sweet, salty, and fatty food preference and overall dietary consumption 30 days after the day three refeed visit. Based on this data, we estimated that 10 days after the start of the fasting, salty taste recognition, sweet taste detection, and sweet taste recognition thresholds decreased significantly, salty taste intensity ratings increased significantly, and sweet taste intensity ratings decreased significantly. We also have preliminary data that prolonged water-only fasting followed by refeeding on an exclusively whole-food-plant diet may reduce salty/fatty and sweet/fatty food liking, reduce sugar intake, and increase vegetable intake. These results support further research into the effects of fasting and diet on taste function and food likability and consumption.

A Six-Week Follow-Up Study on the Sustained Effects of Prolonged Water-Only Fasting and Refeeding on Markers of Cardiometabolic Risk

“…A main criticism of restrictive diets is their lack of long-term adherence [ 4 ], but we found that six weeks after returning home, there was an improvement in dietary adherence. This may be due to the potential effects of fasting on taste adaptation, particularly on salty and sweet food sensitivity, which may reduce the need for added salt, oil, or sugar, and allow for better adherence [ 36 ]. There are still unanswered questions about how an SOS-Free Diet impacts short- and long-term health outcomes, and whether individual dietary changes such as the addition of leafy green vegetables versus the elimination of added salt, oil, or sugar, impact health.…”

“…It is widely reported that humans have practiced therapeutic water-only fasting for more than two thousand years and there is more than a century of published literature on the physiological and clinical effects of water-only fasting in humans. Over the past decade, clinical research into the beneficial and adverse health effects of water-only fasting has progressed with a level of scientific rigor not previously reported [ 6 , 7 , 8 , 9 , 10 , 26 , 36 ]. Nonetheless, there is still a concern about the safety and practicality of prolonged water-only fasting in humans [ 4 ].…”

Prolonged Water-only Fasting is a Safe and Feasible Treatment Option for Managing Stage 1 and 2 Hypertension

“…Participants stayed onsite at a residential fasting center in order to receive medical supervision while prefeeding, fasting, and refeeding for a median (range) of 2 (1-4), 11 (7-40), and 5 (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17) days, respectively (ST3). Participants were instructed to continue eating an SOS-free diet while offsite between EOR and 6wFU visits and did not receive further dietary instruction thereafter.…”

“…[9; 10; 11] Preliminary research suggests that medically supervised, prolonged water-only fasting followed by an exclusively whole-plant-food diet free of added salt, oil, and sugar (SOS-Free Diet) has a very low risk of causing a severe or serious adverse event, results in immediate and sustained improvements in blood pressure and other biomarkers of CVD risk, and may improve adherence to diet and lifestyle modifications. [12; 13; 14; 15; 16] In order to continue evaluating if the intervention has potential as a HTN treatment, we conducted a single-arm pre-post interventional trial with the primary aim of assessing safety and feasibility in people with stage 1 and 2 hypertension by systematically collecting and reporting adverse events and treatment deviations as well as study retention rate, ability to complete minimal fast length, and self-reported intervention acceptability. Additionally, we measured the immediate, sustained, and long-term effects of the full intervention on BP and other cardiometabolic risk factors.…”