Longer IF 1-2x a week: This is taking a longer fasting period of say for up to 24 hours and repeating 1-2x a week. Note that 24 hours is not skipping a whole day, as stopping to eat on 6pm Tues and then having your next meal at 6pm Wed is 24 hours.
http://www.theiflife.com/intermittent-fasting-101-how-to-start-part-i/
Now, there are a few different ways to take advantage of intermittent fasting: 1  Regularly eat during a specific time period. For example, only eating from noon-8 PM, essentially skipping breakfast. 2  Skip two meals one day, taking a full 24-hours off from eating.
https://www.nerdfitness.com/blog/a-beginners-guide-to-intermittent-fasting/
Thats not healthy, you should just eat fruit and veggies and drink water, instead of trying to do a 30 day water fast. You might throw your system off, as in your blood sugar may be unbalanced and it will make you weak and tired because your body need some type of food to fuel off of. Water will not fuel you.
http://www.xmms.org/qna/How_long_should_you_fast_before_doctor_appointment-qna1055301.html
There are multiple ways to “do” intermittent fasting: 1  Fast and feast regularly: Fast for a certain number of hours, then consume all calories within a certain number of hours. 2  Eat normally, then fast 1-2x a week: Consume your normal meals every day, then pick one or two days a week where you fast for 24 hours.
https://www.nerdfitness.com/blog/a-beginners-guide-to-intermittent-fasting/
Fasting is needed because when they are testing your blood, if you have ingested something and have not given it enough time to completely become a part of your body, it will retain in your blood and give higher readings so make sure you fast long enough before you go for your physical.
http://www.xmms.org/qna/How_long_should_you_fast_before_doctor_appointment-qna1055301.html
Your doctor may recommend a certain time period for fasting; however, the standard amount of time is about eight to 12 hours of no food before having blood drawn. Schedule your blood test for early in the morning so you’ll only need to fast overnight to meet requirements. Fast for eight hours before a glucose test. The test is typically conducted in the morning while your body is still in a resting place for a more accurate reading. You must fast at least 12 hours before taking a cholesterol blood test to get an accurate reading on triglycerides.
https://www.leaf.tv/articles/how-long-to-fast-before-a-blood-test/
Be careful not to fast too frequently; allow your body sufficient time to rebuild nutritional reserves. Two days per week is too frequent, as is one week every month. Recommended fasting times for regular, occasional maintenance and rebalancing are one day per week and/or 3 days per month and/or 10 days yearly.
http://www.allaboutfasting.com/how-long-should-you-fast.html
Intermittent Fasting 101. The biggest question I have gotten since starting this site (The “IF” Life) in 2008, is how to effectively use “Intermittent Fasting” (also known simply as “IF”, hence the name of the site) to achieve their goals and maximum results.
http://www.theiflife.com/intermittent-fasting-101-how-to-start-part-i/
In fact, I have been intermittent fasting for the past three months or so while building muscle, with minimal increase to my body fat percentage. I still eat the same number of calories I was consuming before, but instead of eating all damn day long, I condense all of my calorie consumption into an eight hour window.
https://www.nerdfitness.com/blog/a-beginners-guide-to-intermittent-fasting/
The length of your transition periods can be based upon the length of the fast. You would take half the number of days of the fast for each transition period, essentially doubling the number of days between start and finish. So a 10 day fast would then require 20 days of attention and commitment from you. A three day fast would take 6.
http://www.allaboutfasting.com/how-long-should-you-fast.html
how long is considered fasting
A fasting is considered longer, for up to a period of 24 hours, and repeating one to two times in a week. Taking a longer fasting period of say for up to 24 hours and repeating once or twice per week is considered fasting.