But while these diets have gained popularity, there have been only a few longitudinal studies on whether they actually lead to sustained weight loss. (U.S. News & World Report has a breakdown of past research into fasting diets.) Now there’s a new credible study to add to the mix: This 50-week study of 150 obese and overweight adults published in The American Journal Of Clinical Nutrition found that the 5:2 fasting diet was “equivalent but not superior to” conventional dieting in terms of weight loss and the prevention of metabolic diseases.
For Roman Catholics, fasting, taken as a technical term, is the reduction of one's intake of food to one full meal (which may not contain meat on Ash Wednesday and Fridays throughout Lent) and two small meals (known liturgically as collations, taken in the morning and the evening), both of which together should not equal the large meal. Eating solid food between meals is not permitted. Fasting is required of the faithful between the ages of 18 and 59 on specified days. Complete abstinence of meat for the day is required of those 14 and older. Partial abstinence prescribes that meat be taken only once during the course of the day. Meat is understood not to include fish or cold-blooded animals.
The general idea behind the 5:2 diet is calorie restriction on the two (non-consecutive) given days. That is, for two of the 7 days in each week, you eat very low calorie (but high in nutrition) foods, while the other 5 days you can eat what you would usually eat. This diet isn’t a full fast (as in water only), but is a carefully planned eating plan for a couple of days each week.

In addition to our attitudes towards God and our stance before man, our motives must also be correct. We should fast in order to further the building up of God’s kingdom by seeking to minister to others. The prophet Isaiah received from the Lord the acceptable motives for our fasts: “Is not this the kind of fasting I have chosen: to loose the chains of injustice and untie the cords of the yoke, to set the oppressed free and break every yoke? Is it not to share your food with the hungry and to provide the poor wanderer with shelter -- when you see the naked, to clothe him, and not to turn away from your own flesh and blood?” (Isaiah 58:6-7). 

^ Guéranger, Prosper; Fromage, Lucien (1912). The Liturgical Year: Lent. Burns, Oates & Washbourne. p. 8. St. Benedict's rule prescribed a great many fasts, over and above the ecclesiastical fast of Lent; but it made this great distinction between the two: that whilst Lent obliged the monks, as well as the rest of the faithful, to abstain from food till sunset, these monastic fasts allowed the repast to be taken at the hour of None.

Research more about IF and learn outside of what I share to see if there is a different style of IF that is a better fit for you and your needs. While there is widely available research on the benefits of IF, you should also learn more about the potential of negative effects of fasting on sleep, alertness, cognitive-motor performance, mood and for those with a previous history or susceptibility with eating disorders.


Insulin rises when we eat, helping to store the excess energy in two separate ways. Sugars can be linked into long chains, called glycogen and then stored in the liver. There is, however, limited storage space; and once that is reached, the liver starts to turn the excess glucose into fat. This process is called De-Novo Lipogenesis (meaning literally Making Fat from New).
Another study, this one out of the University of Southern California, discovered that when 71 adults were placed on a five-day fast (eating between 750 and 1,100 calories a day) once every three months, they lost an average of 6 pounds, reduced inflammation levels and their waistlines and lost total body fat without sacrificing muscle mass. (2) If you want to lose weight and lose belly fat, fasting even irregularly could be the key.
And there are many plans, because there are many schools of thought about what’s considered fasting, what food or drink should be consumed during eating windows, and how long these windows should last. Here are a few of the most common methods: Intermittent fasting means eating normally four or five days a week and consuming minimal calories on two or three nonconsecutive days. Time-restricted eating requires setting a window for consuming food, such as 7 a.m. to 7 p.m, and having nothing but noncaloric liquids the rest of the time. The “fasting mimicking diet” involves eating a small number of calories daily for a specific period of time — say five consecutive days every other month. These protocols all have benefits and drawbacks. One approach may work well for some while being entirely unsustainable for others.

Hi I work really crazy hours, mostly over night. How am I able to do this correctly when it’s hard for me to keep a regular eat and fast regimen when I sleep a lot during the day. And my schedule at work can be all over the place not just one set time frame. I would really like to try this but I need some help trying to figure out time frames that can fit my schedule.


Mattson points out that, from an evolutionary perspective, the brain power that fasting generates makes sense. Mammals typically go days without food, often hunting on an empty belly. Semi-starved animals with enhanced smarts and energy would be more likely to obtain food and live another day. “If you are that wolf or lion, now a week with no food, you better be able to focus your mind and concentrate on what you need to do to get food,” he says.
Fasting from food is not necessarily for everyone. Some health conditions keep even the most devout from the traditional course. However, fasting is not limited to abstaining from food. As Martyn Lloyd-Jones said, “Fasting should really be made to include abstinence from anything which is legitimate in and of itself for the sake of some special spiritual purpose.”
Reduces inflammation: Lowering inflammation is key to losing weight, boosting longevity, and reducing your risk of major illnesses such as Alzheimer’s and cancer. That’s why it’s at the core of the Bulletproof Diet. Intermittent fasting decreases oxidative stress and inflammation across the board, including inflammatory markers such as adiponectin, leptin, and brain-derived neurotrophic factor.[9]
According to a research published in Cell Metabolism, fasting for 12+ hours most days may promote weight loss, prevent disease and promote longevity. The researchers, who divided the mice into four diet groups and categorised them into different feeding schedules, found that mice fasted for at least 12 hours and kept their eating within a set 12-hour time frame experienced significant weight loss compared to mice eating the same diet but with liberty to eat all day long. 

“Cycles of fasting can reset and rejuvenate the human body,” said Valter Longo, director of the Longevity Institute at the University of Southern California. Periods with no food, he said, help the body eliminate and replace damaged cells with new ones through a process called autophagy (the study of which recently garnered a Nobel Prize). (Longo is a leading fasting researcher but he’s pretty dug in — with a book about fasting, and a company that sells fasting products. He says he donates all the proceeds from the company and the book to health charities.)
There may also be other intermittent fasting benefits: A 2017 study from the University of Southern California followed 71 adults who were placed on a low-calorie, fasting-mimicking diet for five days each month for three months. After following the diet, researchers found that the diet reduced cardiovascular risks, including blood pressure, inflammation, and body fat, in participants. A 2018 study from the British Journal of Nutrition backs this up after overweight participants followed the 5:2 method and saw improvements in their triglyceride levels and blood pressure. Other studies have also shown that IF may help with relieving MS symptoms, but more studies are needed on a larger scale and for a longer period of time to support these claims.
^ Stravinskas, Peter M. J.; Shaw, Russell B. (1 September 1998). Our Sunday Visitor's Catholic Encyclopedia. Our Sunday Visitor. ISBN 9780879736699. The so-called black fast refers to a day or days of penance on which only one meal is allowed, and that in the evening. The prescription of this type of fast not only forbids the partaking of meats but also of all dairy products, such as eggs, butter, cheese and milk. Wine and other alcoholic beverages are forbidden as well. In short, only bread, water and vegetables form part of the diet for one following such a fast.
Lastly, I always start each day (on fasting days I take them with my meal) with a dose of bioavailable multivitamins to fill any nutritional gaps. If you plan on doing the same in the future, just remember to go for all-natural and organic multi-vitamin because synthetic vitamins tend to have no oral bioavailability. New Chapter (the one I linked above) has a high oral bioavailability and is one of the best multis on the market.

Fasting ramps up your stem cell production.[6] Stem cells are like biological playdough — your body turns them into any kind of cell it needs and uses them to replace old or damaged cells, keeping you younger on a cellular level. Stem cells are great for your skin, joints, old injuries, chronic pain, and more. You can try stem cell therapy…or you can just fast.
There may also be other intermittent fasting benefits: A 2017 study from the University of Southern California followed 71 adults who were placed on a low-calorie, fasting-mimicking diet for five days each month for three months. After following the diet, researchers found that the diet reduced cardiovascular risks, including blood pressure, inflammation, and body fat, in participants. A 2018 study from the British Journal of Nutrition backs this up after overweight participants followed the 5:2 method and saw improvements in their triglyceride levels and blood pressure. Other studies have also shown that IF may help with relieving MS symptoms, but more studies are needed on a larger scale and for a longer period of time to support these claims.
Disclaimer: The entire contents of this website are based upon the opinions of Dr. Mercola, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Mercola and his community. Dr. Mercola encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional. If you are pregnant, nursing, taking medication, or have a medical condition, consult your health care professional before using products based on this content.
WHAT DO YOU THINK? - We have all sinned and deserve God's judgment. God, the Father, sent His only Son to satisfy that judgment for those who believe in Him. Jesus, the creator and eternal Son of God, who lived a sinless life, loves us so much that He died for our sins, taking the punishment that we deserve, was buried, and rose from the dead according to the Bible. If you truly believe and trust this in your heart, receiving Jesus alone as your Savior, declaring, "Jesus is Lord," you will be saved from judgment and spend eternity with God in heaven.
If you're looking to lose weight, this isn't a problem. And even if you're happy with your weight, this won't prove to be too much of an issue if you follow the daily fasting or weekly fasting schedules. However, if you're fasting for 24 hours per day on multiple days per week, then it's going to be very difficult to eat enough of your feast days to make up for that.
For charismatic Christians fasting is undertaken at what is described as the leading of God. Fasting is done in order to seek a closer intimacy with God, as well as an act of petition. Some take up a regular fast of one or two days each week as a spiritual observance. Members of holiness movements, such as those started by John Wesley and George Whitefield, often practice such regular fasts as part of their regimen.
Those desiring to receive Holy Communion keep a total fast from all food and drink from midnight the night before (see Eucharistic discipline). The sole exception is the Communion offered at the Easter Sunday midnight liturgy, when all are expressly invited and encouraged to receive the Eucharist, regardless of whether they have kept the prescribed fast.
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