Fasting Diets Description:
Intermittent fasting diets are a relatively recent area of research. They are an example of a “combination” energy restriction.
It is recommended that people follow a VLED anywhere from one to three days a week, except the energy comes from food rather than formulated meal replacement products.
The other days, people choose to follow either an RED or LED. Although there are only a small number of research studies to date, this approach appears to suit some people and preliminary research looks promising.
Currently, there are still not enough good quality research studies to be sure whether this approach improves health or well-being long-term. Future research trials will help to work this out, so watch this space.
An intermittent fasting diet can lead to a range in weight loss outcomes, depending on the reduction of kilojoule intake on non-fasting days. The level of difficulty in sticking to this type of diet will also vary, being harder on fasting days compared to non-fasting days.
What can you eat:
On the diet plans where the fasting diet recommends reducing intake rather than completely eliminating food, the target is to consume around a quarter of a normal days intake which is commonly around 2000–2500kJ per day for most people.
The 5:2 diet plan suggests you eat normally for five days, then fast for two days of the week.
Advantages of fasting diets:
- Fasting days lead to overall kilojoule restriction across the week and so can be effective for weight loss
- Intermittent fasting diets may be as effective as other kilojoule restricted diets
Disadvantages fasting diets:
- For some, it may be very difficult to stick to or may lead to cravings and over-eating or stress
- Insufficient evidence on the long-term effects of intermittent fasting and whether this impacts on a person’s metabolism is not clear
- May lead to malnutrition if a person’s usual diet is nutritionally inadequate to begin with
- Not suitable for pregnant women
- May not be suitable for people with diabetes. They will need close medical supervision by a doctor due to the need to carefully monitor medications and health