Recently, I have been asked a lot of about something called Intermittent fasting (IF). I went straight to the research to look for the possible benefits and adverse effects of such a diet.
Personally, I don’t think this kind of diet would be unhealthy. As with anything, the more research out there the more confusing something can become. Sometimes the more we search the less we know for sure, always saying we need to know more. This is okay. I’m about to tell you everything I have found. Both pro’s and con’s; Both sides of the story. Whether or not you should do a diet like this is completely up to you, obviously you should discuss all of this with your doctor, your nutritionist, or fitness instructors.
There is a chance, that when you ask your doctor about IF, they may respond with “not sure, I’d have to look into it”. It is way better to get that response rather than to hear “its great” or “its terrible and unhealthy don’t do it”. There are different types too! There is Alternate IF, Modified IF and Time Restricted IF. So many different kinds! So lets get into what each type means. Alternate IF
This means that 2 days a week you do not eat and do not drink anything. This is known as the 5:2. On the other days, you eat like you normally would.
You alternate between fasting and eating days. Notice I said normally, this does not mean binge eat unhealthy fatty foods like 3 big macs and a shake because you’ve fasted for 24 hours the previous day.
Research found that this kind of IF reduced fasting insulin and glucose levels. However, the effects were not much different from regular caloric restriction while eating low calories everyday of the week. One study, looked at a combination of studies. Some found that IF lowered triglycerides (TG), cholesterol, certain cancer risk factors and inflammatory markers.
Weight loss was also noted. However, other studies found that although these things to occur, LDL (BAD cholesterol) also increased. Another issue was that people in the study complained of constant hunger on fasting days, which “did not decrease over time”, so it might not be an achievable intervention to improve the health of a community
This is similar to Alternate IF, the difference is that on the “fasting days” instead of not eating or drinking anything at all, you only eat or drink 20-25% of what you normally would.
Overall results from many studies show that there is weight loss, with some improvement in sugar levels, inflammatory markers, insulin resistance.
Very similar to the Alternate IF. However, they were not able to show that this kind of calorie restriction was any better than any other type of diet in which calories are restricted. Some people reported feeling less tension and anger and a positive effect on self-confidence. Other people reported headaches, low energy, feeling cold and irritable. Clearly this diet does not have the same effect on everyone, so it’s important to listen to your body and change your diet and exercise regimens to you specifically.
Time Restricted IF
These diets generally have a fasting interval of about 12-20 hours. This means the remaining 4-8 hours are the eating permitted hours. There are some differences. You can either do 1 meal a day (lunch usually), OR you can use your eating interval to space out 3 meals in the day of equal calories as if you would to have the 1 meal/day. Sounds confusing so I hope I didn’t make that worse. This type of dieting has similar results to the above two. Lower cholesterol, glucose, insulin, and some other factors, which would improve your immunity (ability to fight infection) and improved insulin sensitivity. Comparing the 1 meal a day to the 3 meal a day type of diets: There was higher weight loss in those who only consumed 1 meal/day.
Yes! Those who only ate 1 meal a day complained of feeling more hungry the morning after their fast. Who likes to feel hungry? I definitely don’t, which is why this diet wouldn’t be for me (but it still could be for you).
That about explains the benefits and downfalls of each type of IF. But I am sure you just want to know whether or not this is a good diet, or if it’s even good for YOU. Am I right? Okay, here is the bottom line:
- Any type of fasting such as over night fasting has shown to level your metabolism and put it into a “steady state”. Meaning not high and not low just regulated.
- Any of the above 3 can lead to weight loss, between 3-8%. However, other diets that are low in calories can lead to a weight loss of 4-14%. These diets as well as any other low cal diet can lower visceral fat, insulin resistance, fasting insulin and glucose. So there are some benefits, but these can be reached through other less strict diets as well.
- Alternating between fasting and eating days may be the worst one. Not because its unhealthy as it has similar benefits as the other 2, but because many people complain of hunger, and hunger is definitely not something you want to feel.
- There are some benefits as you can see, but everyone reacts differently. These kinds of diets can also alter your sleeping patterns, your mood and exercise endurance.
Okay, that’s it. Intermittent fasting is a thing now and it’s becoming more popular. Regardless of which diets you choose to follow, do your research. Ask people who do them, and ask them for guidance. Make sure you are keeping track of yourself and monitoring how you feel both in energy, mood and overall
wellbeing. And if you feel great, healthy, strong, and energized then by all means continue doing what you’re doing. Make sure you consult with your doctors too. Oh… I forgot to mention this one last thing. IF in combination with exercise has much stronger effects on your weight!
Okay now I’m done!