 Hey, everybody. Dr. O here. In this video, we're going to cover alternate day fasting or ADF. Alternate day fasting is my favorite form of fasting for weight loss, but I had a lot of weight to lose, so it may not be for you. Again, we'll cover the pros and cons of each of these different types of fasting programs throughout these videos. I credit a ton of my weight loss success to alternate day fasting. Now, I did start exercising and sleeping and managing my stress and I changed my diet. I did lots and lots of things, but if you're looking at the calorie deficit that I had to be in over time to lose 165 pounds in a year, alternate day fasting is the only way that I could have got there. I've explained that in the section on calorie cycling and throughout this course. Research shows that alternate day fasting has been proven to be a good weight loss strategy. Number two, research has also shown that if you add exercise to alternate day fasting, you can actually make it twice as effective, so exercise is not necessary, but it will accelerate your fat loss efforts. The first thing I want to talk about with alternate day fasting is it's not a 24-hour fast. If you think, well, I eat one day and I don't eat the next, does that mean I went 24 hours without eating? No. You actually go 36 hours without eating because you're sleeping twice. You see here that Monday you eat and then Monday night you have supper. Let's say supper ends at 7 o'clock and then you start your fast then. You sleep. You wake up Tuesday. You don't eat. You go to sleep Tuesday night and then you wake up Wednesday morning at, let's say, 7 in the morning to eat. That is a 36-hour fast. Alternate day fasting is really your cycling between 36-hour windows where you're fasting and then 12-hour windows where you're eating. We've already covered that when you're eating, I expect you to eat 25 or 30 or even 35% more calories than you normally would on those eating days, but you'll still be in a really, really good calorie deficit. That's one of the reasons I love alternate day fasting is during that 36-hour window you're sleeping twice and fasting, the best time to fast is when you're asleep because you're not thinking about it. You'll see here though with alternate day fasting, and I looked at this as a con and I'll explain how I modified it for myself, is you're basically fasting three and a half days a week because there's an odd number of days in a week. In the first week here, you're fasting on Tuesday, Thursday, and Saturday. The second week you're fasting Monday, Wednesday, Friday, Sunday. Again, that's perfectly fine, but I will show you how I modified it because I like to be on a schedule where I know what's happening on Monday and I know what's happening on Tuesday. As much as I love alternate day fasting, I found ways to modify it for myself and you should too. First of all, what does the science say? The effects of intermittent fasting on body composition and clinical health markers in humans. These were fasting trials that were up to 24 weeks long. This was effective at reducing body weight and body fat, lowered cholesterol, lower triglycerides, lower blood sugar, lower insulin, all positive things. This study was on people that were obese, but also people that were overweight and people that were normal weight. The more fat you have to lose, the more effective this will be. Another study, alternate day fasting improves physiological and molecular markers of aging and healthy, non-obese humans. In this study, they found that participants consumed 35% fewer calories, so not 50% because they were eating more on their eating days and that's perfectly fine, but a 35% reduction in calories will lead to rapid and effective weight loss. During this study, the average person lost 7.7 pounds, so they were doing 36 hours of fasting and then here's the key, 12 hours of unlimited eating over a four-week period. They lost almost two pounds a week and during their 12-hour windows, they weren't limited at all in what they were eating, so fast, eat, fast, repeat. Another study. Effects of alternate day fasting on weight loss, weight maintenance, and cardio protection among metabolically healthy obese adults, a randomized clinical trial. First of all, what's a metabolically healthy obese person? This would be someone that is obese because of their BMI, but they don't have risks factors for metabolic disease or metabolic syndrome. Their triglycerides are normal, blood pressure is normal, et cetera, but this study found same thing. Not only is it really good at helping you lose weight, but it can be a really effective weight maintenance tool and we'll talk about that a little bit more. What are the pros of alternate day fasting? To me, this is the best approach if you have more than 40 pounds to lose. If you have 50, 70, 100 pounds to lose, there's really no risk in fasting for 36 hours once you get used to it. The more fat you have to lose, the more aggressive you can be and this is the most aggressive of any of the fasting protocols that I'm going to share. Remember, the more aggressive your weight loss, the more you need to monitor signs that you're losing lean tissue because you're losing weight so quickly and the more often you should take breaks. You should take what I like to call weight maintenance breaks and I'll teach you later about how we take periods of time where we settle in a new weight, we learn how to maintain our weight and then we can get back into aggressive dieting. Let me show you, this was my biggest con. The cons of alternate day fasting, of course, it's hard until you get used to it, but the hardest part for me was scheduling. I've told you in multiple places that I wanted to fast on days when I was busiest. For example, Monday and Wednesday are my two busiest days at work. Those are days that I always want to fast. Then also, I want to keep an exercise schedule. I don't exercise every other day. I exercise Tuesday, Thursday, Saturday, Sunday. I wanted to keep my fasting schedule set and my exercise schedule set. I modified this. Instead of doing alternate day fasting, you could just do three or four fasts a week. What I would do is I would fast three times one week and then three and a half or four the next week. Let me show you that. Let me show you my fasting schedule. This is what I liked because it did allow me, it allowed me to fast on the days when I was busiest, which makes fasting easier and allowed me to eat on the days of exercise. I would fast, you see, the first week, I would fast Monday, Wednesday, Friday. Then I would exercise Tuesday, Thursday, Saturday, Sunday. I was eating on my exercise days, which is very important because you want to fuel performance and you want to tell your body that it's okay to build or at least maintain muscle. Then I was fasting on the days that I was the busiest. You only see the next week what I would do. Remember, I have a lot of weight to lose. You could just do that. You could fast three days a week and call it a modified alternate day fasting program. I still wanted to average three and a half fasting days a week. The next week, I would fast Monday, Wednesday, Friday. On Sundays, I would either fast or do what's called a protein sparing modified fast, where I would consume definitely under 1,000 calories. Those calories would almost all come from protein. Then I would do a really light exercise on that day because I wasn't eating. My fasting program that I used to lose 165 pounds, I averaged three and a half fast per week, but I never really ever fasted alternate day. Three fast one week for the next, but unless you have a lot of weight to lose, fasting three days a week is more than enough. I've learned over time. The longer I've done this, the less I recommend being super aggressive. Fasting three times a week, 36 hours, three times a week is already plenty aggressive and you will reach your goals. What are the other cons of alternate day fasting? It's tough and take it used to it. I don't tell people to jump right in. Follow all the advice that I'm giving you in this program to the letter. If you're new to intermittent fasting, then ease into it. Maybe start with a modified alternate day fasting program like I'm going to be showing you in the next video. Maybe start with time restricted feeding and slowly work your way to alternate day fasting. These are all things you can do. Then I'll have a troubleshooting section later, but be sure to follow my advice on hydration and getting your electrolytes because if you are going 36 hours without eating, most of the side effects of alternate day fasting do come from not staying hydrated and not getting your electrolytes. We'll cover that in the troubleshooting section. This is alternate day fasting, the pros, the cons, how you can use it, how I use it. I hope this helps. Have a wonderful day. Be blessed.