Scientists continue to unravel the benefits of caloric restriction and intermittent fasting. The simple act of limiting food intake increases lifespan in animal models and reduces age associated disorders such as diabetes and heart disease. A report published in the New England Journal of Medicine reviewed extensive research on intermittent fasting and caloric restriction. Multiple mechanisms were identified by which these dietary changes are expected to have a beneficial impact on health. The report found three different intermittent fasting regimens to be just as effective as true fasting at inducing benefits of caloric restriction. Intermittent fasting, also known as time-restricted eating, helps regulate the expression and activity of proteins and other cell factors known to influence health and aging. Those able to adjust their time of food intake may experience biological changes that boost resistance to disease and help extend lifespan.
Modern humans have gotten used to eating three meals a day along with frequent snacks. This constant intake of food has profound adverse effects on our metabolism and health. Digesting and processing food is a complex, energy intensive process that can accelerate pathological aging processes. Studies have consistently shown that intermittent fasting is superior to constant eating in many ways. All intermittent fasting regimens have regular periods of eating when food and calories are not restricted. But their benefit comes from restricting the amount of time that one is eating, and alternating it with relatively long periods of not eating or eating very little. Three types of intermittent fasting that have been most studied in animal models and human trials and discussed in the New England Journal of Medicine are:
1. Alternate-day fasting. In this regimen, food intake is normal for one day followed by a day of fasting or severe caloric restriction. The pattern is continued indefinitely.
2. Time-restricted feeding. In this model, intake of food is restricted to only a small number of hours per day. The rest of the day is spent fasting. One common pattern is to restrict food intake to six hours during the day, while fasting the remaining 18 hours. (Other programs advocate for about 16 hours a day of fasting and an eight-hour eating period.)
3. 5:2 intermittent fasting. One of the most popular forms of intermittent fasting restricts calories (with a limit of 500-700 calories per day) on just two days of each week. Normal food intake is fine on the other five days. These intermittent fasting plans are often easier to adhere to than daily caloric restriction. These three patterns of eating are believed to be equally effective for improving health.
The fed state is the period of time when food has recently been consumed. The fasting state occurs after several hours without eating, when nutrients are less available and the body must conserve energy and resources. Cell metabolism changes dramatically between these two different states. In the fed state, when nutrients are plentiful, energy is stored, often as fat. In the fasting state, as carbohydrates from previous meals are used for energy, fat and other energy-storage compounds are broken down. Some of these fats are converted by the liver into ketones, substances that provide an alternative fuel source for the brain and other tissues. This metabolic shift to ketone metabolism takes time. Ketones in the blood begin to rise 8 to 12 hours after fasting begins. Most people who eat throughout the day, every day, never enter a fasting state.
In a recent New England Journal of Medicine report, intermittent fasting can benefit many. Some of the takeaways were:
-Decrease free radicals
-Cellular response with increase glucose utilization, increase stress resistance, and decreased inflammation
I’ve incorporated IF into my weekly routine and haven’t looked back. Maintaining ideal weight, reduction of insulin resistance, better cholesterol numbers, and appetite control have been some personal benefits I’ve seen myself. Patients who have a history of hypoglycemia, severe mood disorders, and adrenal problems may not do as well with this type of protocol. Many people want to lose some extra pounds of what they gained from the stressful year of 2020. This is very easy to incorporate. Next time you are in the office we can customize an individual plan for intermittent fasting with a protocol of supplements tailored to your needs.