I do it at least 5 days a week... Fasting that is.

Fasting has no standard duration, as it is nearly the absence of eating. Anytime you are not eating, you are fasting.
Food is easily available these days, but you choose not to eat it. This can be for any period of time, from a few hours up to a few days. You can begin your period of fasting anytime you choose, and you may also end a fast whenever you choose.
You can start or stop a fast for any reason or no reason at all.
Who should NOT fast?
Underweight (BMI under 18.5)
Pregnant- you need extra nutrients for your child.
Breastfeeding- you need extra nutrients for your child.
A child under 18- you need extra nutrients to grow.
You can fast, but may need supervision , under these circumstances:
If you have diabetes mellitus.
If you take prescription medication.
If you have gout or high uric acid.