Jeremiah, I don’t think the author is suggesting that TRF in the later hours of the day is bad, but rather that it is DIFFICULT. The key finding in this study is that the 07:00-15:00 eaters had a reduced appetite (in other words, didn’t find it very hard to follow this regimen), whereas other approaches have been found to be kind of difficult for some.
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60 year old and just started IF a week ago. I eat from noon to 8pm. The noon start works for me because I’m not starting my day with the thought of food! I LOVE FOOD AND LOVE TO EAT! I am moving away from some bad habits and it doesn’t seem that difficult for me with IF! Just one week in and I do feel better. Can’t wait till I’ve got a month under my belt.

The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used primarily to treat difficult-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than carbohydrates. Normally, the carbohydrates contained in food are converted into glucose, which is then transported around the body and is particularly important in fueling brain function. However, if little carbohydrate remains in the diet, the liver converts fat into fatty acids and ketone bodies. The ketone bodies pass into the brain and replace glucose as an energy source. An elevated level of ketone bodies in the blood, a state known as ketosis, leads to a reduction in the frequency of epileptic seizures.[1] Around half of children and young people with epilepsy who have tried some form of this diet saw the number of seizures drop by at least half, and the effect persists even after discontinuing the diet.[2] Some evidence indicates that adults with epilepsy may benefit from the diet, and that a less strict regimen, such as a modified Atkins diet, is similarly effective.[1] Potential side effects may include constipation, high cholesterol, growth slowing, acidosis, and kidney stones.[3]


In many developing countries, the ketogenic diet is expensive because dairy fats and meat are more expensive than grain, fruit and vegetables. The modified Atkins diet has been proposed as a lower-cost alternative for those countries; the slightly more expensive food bill can be offset by a reduction in pharmaceutical costs if the diet is successful. The modified Atkins diet is less complex to explain and prepare and requires less support from a dietitian.[55]

Carbohydrates have been linked to this skin condition, so cutting down on them may help. And the drop in insulin that a ketogenic diet can trigger may also help stop acne breakouts. (Insulin can cause your body to make other hormones that bring on outbreaks.) Still, more research is needed to determine exactly how much effect, if any, the diet actually has on acne. 


The ketone bodies are possibly anticonvulsant; in animal models, acetoacetate and acetone protect against seizures. The ketogenic diet results in adaptive changes to brain energy metabolism that increase the energy reserves; ketone bodies are a more efficient fuel than glucose, and the number of mitochondria is increased. This may help the neurons to remain stable in the face of increased energy demand during a seizure, and may confer a neuroprotective effect.[56]


A Cochrane systematic review in 2018 found and analysed eleven randomized controlled trials of ketogenic diet in people with epilepsy for whom drugs failed to control their seizures.[2] Six of the trials compared a group assigned to a ketogenic diet with a group not assigned to one. The other trials compared types of diets or ways of introducing them to make them more tolerable.[2] In the largest trial of the ketogenic diet with a non-diet control[16], nearly 38% of the children and young people had half or fewer seizures with the diet compared 6% with the group not assigned to the diet. Two large trials of the Modified Atkins Diet compared to a non-diet control had similar results, with over 50% of children having half or fewer seizures with the diet compared to around 10% in the control group.[2]
Avoid sweetened drinks. Drinks that are sweetened, whether artificially or naturally, will have little nutritional value and add lots of empty calories to your diet. Do not drink fruit juice or other sweetened drinks. Even natural sugars will increase your daily calorie intake and prevent weight loss. If you chose to drink juice, do not exceed 4 oz per day (1/2 cup). Instead of drinking sweetened beverages throughout your day, drink unsweetened, calorie-free beverages. Some beverages to avoid include:
The Mayo Clinic Diet is generally safe for most adults. It does encourage unlimited amounts of vegetables and fruits. For most people, eating lots of fruits and vegetables is a good thing — these foods provide your body with important nutrients and fiber. However, if you aren't used to having fiber in your diet, you may experience minor, temporary changes in digestion, such as intestinal gas, as your body adjusts to this new way of eating.
When you eat less than 50 grams of carbs a day, your body eventually runs out of fuel (blood sugar) it can use quickly. This typically takes 3 to 4 days. Then you’ll start to break down protein and fat for energy, which can make you lose weight. This is called ketosis. It's important to note that the ketogenic diet is a short term diet that's focussed on weight loss rather than the pursuit of health benefits. 

It has totally regulated my appetite and normalised my relationship with food. My obsessive thoughts have completely subsided, my black and white thinking around food has gone, and I no longer binge! This is amazing. For the first time in my adult life I feel like I know what it is like to have a normal relatinoship with food. I eat when I eat, a range of healthy whole foods and occasional less healthy foods. In normal amounts. In manageable amounts. And when my meal is over, I stop! Normal for others, a seeming impossibility for me (and, I’m guessing, others with eating disorders).

It is possible to combine the results of several small studies to produce evidence that is stronger than that available from each study alone—a statistical method known as meta-analysis. One of four such analyses, conducted in 2006, looked at 19 studies on a total of 1,084 patients.[23] It concluded that a third achieved an excellent reduction in seizure frequency and half the patients achieved a good reduction.[18]
The senor governor got up, and by Doctor Pedro Recio's directions they made him break his fast on a little conserve and four sups of cold water, which Sancho would have readily exchanged for a piece of bread and a bunch of grapes; but seeing there was no help for it, he submitted with no little sorrow of heart and discomfort of stomach; Pedro Recio having persuaded him that light and delicate diet enlivened the wits, and that was what was most essential for persons placed in command and in responsible situations, where they have to employ not only the bodily powers but those of the mind also.

Most people who want to lose weight have more than 12 pounds to lose. That’s why even the best weight loss drug in the world can only be an optional complement to other treatment. That’s why this piece of advice is number 18 out of 18. It may be a helpful addition for some people, but the advice higher on the list is what can make the biggest difference, by far.


The day before admission to hospital, the proportion of carbohydrate in the diet may be decreased and the patient begins fasting after his or her evening meal.[19] On admission, only calorie- and caffeine-free fluids[37] are allowed until dinner, which consists of "eggnog"[Note 8] restricted to one-third of the typical calories for a meal. The following breakfast and lunch are similar, and on the second day, the "eggnog" dinner is increased to two-thirds of a typical meal's caloric content. By the third day, dinner contains the full calorie quota and is a standard ketogenic meal (not "eggnog"). After a ketogenic breakfast on the fourth day, the patient is discharged. Where possible, the patient's current medicines are changed to carbohydrate-free formulations.[19]


1 Reference for 5%: Blackburn G. (1995). Effect of degree of weight loss on health benefits. Obesity Research 3: 211S-216S. Reference for 10%: NIH, NHLBI Obesity Education Initiative. Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. Available online: http://www.nhlbi.nih.gov/guidelines/obesity/ob_gdlns.pdf Cdc-pdf[PDF-1.25MB]External
Obviously, it’s still possible to lose weight on any diet – just eat fewer calories than you burn, right? The problem with this simplistic advice is that it ignores the elephant in the room: hunger. Most people don’t like to “just eat less”, as it may result in having to go hungry forever. Sooner or later, a normal person will likely give up and eat, hence the prevalence of “yo-yo dieting”. While it should be possible to lose weight on any diet, some appear to make it easier and some to make it much harder.

Be choosy about carbs. You can decide which ones you eat, and how much. Look for those that are low on the glycemic index (for instance, asparagus is lower on the glycemic index than a potato) or lower in carbs per serving than others. Whole grains are better choices than processed items, because processing removes key nutrients such as fiber, iron, and B vitamins. They may be added back, such as in “enriched” bread.
High blood sugar levels coupled with high blood ketones, on the other hand, will mean that you have a pathologically low level of insulin – something non-diabetics do not suffer from. This can lead to ketoacidosis – a potentially life-threatening condition. If this happens, you’ll need to inject more insulin; if you’re at all unsure of what to do, contact a medical professional or have someone take you to the hospital to be checked out. Coveting really high blood ketones for weight control is not worth the risk for people with type 1 diabetes.
I would like to know what led you to the conclusion to recommend eating in the morning and fasting in the evening instead of the other way around. You do not link any studies here that show TRF in the morning is better than TRF in the evening. You do state “Nighttime eating is well associated with a higher risk of obesity, as well as diabetes.” but I would hazard a guess that alot people that snack into the evening have many other factors at play that could effect their risk of obesity and diabetes and are possibly not fasting at all. I have been doing TRF from 12-8pm every day for almost a year and have seen vast improvements in my health, not least of which is a loss of 70 lbs, so it seems odd to read items 3 and 4 on your 4 ways to use this information for better health. If you have evidence that supports the idea that TRF in the evening is bad then I would like to see it and perhaps change my dieting habbits.
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About 20% of children on the ketogenic diet achieve freedom from seizures, and many are able to reduce the use of anticonvulsant drugs or eliminate them altogether.[18] Commonly, at around two years on the diet, or after six months of being seizure-free, the diet may be gradually discontinued over two or three months. This is done by lowering the ketogenic ratio until urinary ketosis is no longer detected, and then lifting all calorie restrictions.[46] This timing and method of discontinuation mimics that of anticonvulsant drug therapy in children, where the child has become seizure-free. When the diet is required to treat certain metabolic diseases, the duration will be longer. The total diet duration is up to the treating ketogenic diet team and parents; durations up to 12 years have been studied and found beneficial.[9]
Many people choose to forgo food from animal sources to varying degrees (e.g. flexitarianism, pescetarianism, vegetarianism, veganism) for health reasons, issues surrounding morality, or to reduce their personal impact on the environment, although some of the public assumptions about which diets have lower impacts are known to be incorrect.[3] Raw foodism is another contemporary trend. These diets may require multivitamin supplements to meet ordinary nutritional needs.
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