LORI NEdescu,




Board certified sports dietitian, pro athlete, freelance nutrition writer, published author, social content developer & personal chef.

Fasting Q&A

Fasting Q&A

Intermittent Fasting.png

I’m currently deep into writing a book on Fasting. It’s a BIG process and while I hope you all learn a lot and really benefit from the book , but I am benefiting a ton from writing it!! To give you the best information, I’ve been doing my research. All that research has me loving the idea of intermittent fasting (IF) even more… the potential benefits are just so intriguing! And logically, the concept of giving your body a break fro processing food makes sense! Just like you need to sleep, take a rest day from training, etc… REST is okay. There is no harm that comes from not shoveling food in your face for several hours. But like anything, you can do it well or not well, in a healthful way or not.

I’m not going into full detail with fasting her; sorry, you have to wait until Jan 2020 the book! But I do want to address the basics, answer few of your questions, and invite you to do it with me!

Why I’m a FAN!

IF is great because it doesn’t put restrictions on what you eat. There are no ‘good’ or ‘bad’ foods. It is something we can all do, regardless if you’re gluten free, vegan, love veggies or hate them. IF is all about being fasted or fed.

I’m a logical person… and IF and it just makes sense! We know our bodies need rest. Sleep is crucial! Rest days are crucial! Why wouldn’t we need a break from eating and making the body deal with digesting/ processing nutrients. It is during these extended breaks from eating that the body benefits and adapts. Most of us eat all day long, from waking up to just before bed which puts a tremendous about of strain on the body to constantly be digesting and all the biologically processes that accompany food intake. Most of you think that sleep is fasting, but research shows you need to go 12+ hours for benefits and few of us go that long between bites, even overnight.


There are two main forms, Time Restricted Feeding (TRF) or Alternative Day Fasting (ADF) both have benefits, but slightly differently protocol. Pick which works best for life style.

TRF (what I’m currently doing) - This is a daily process of fast + fed periods. Fasting needs to be 12-16 hours with zero calories consumed (nothing!) and the rest of the time you’re eating a nutrient rich (hopefully) diet. Research has shown that 5 days / wk of this is beneficial.

ADF (I’ve done this in the past) - This is a weekly process that involves swapping normal 24 hours of eating with 24 hours of fasting. 5:2 is a popular example of this. On fasting day(s) you can eat 0-25% of your total needs. On fed days, you eat normally. Research has shown 1 fasting day/ wk can be enough.


You guys submitted these on Social.

I’m healthy, so why?
IF has shown to be very useful in preventative care by lowering inflammation and regulating physiological processes. Potential benefits include decreasing the negative effects associated with aging & mental decline, improved cholesterol profile, better glucose sensitivity, better sleep, better digestion, etc etc etc… there are many good health outcomes associated. Taking care of yourself isn’t just about being healthy today, but making sure you’re healthy tomorrow.

Is it good during training & racing?
Yes & No. There are definite benefits to fasted workouts and fasting in general for athletes. But you must take extra care to get what you need outside the fast. Most athletes can do TRF just fine without their training suffering. The exception to that is if you’re a high volume athlete with frequent sessions a day. Athletes with less sessions a week and shorter sessions can do ADF without much difficulty. If you’re in a heavy racing season, I would not do this. Do it in your base training and get the adaptations ahead of when you are racing.

How to regulate blood glucose spikes and dips?
IF does this, you just follow the protocol and your body will learn to improve sensitivity and better control blood glucose/ insulin response. See note below*

Best time frame for success?
Your window of fast/fed hours is up to you. Most of us will benefit more from eating earlier in the day and finishing 3-4 hours before bedtime. But look at your schedule and see what works for you. TRF windows can be flexible meaning as long as there’s 12+ hours of fasting, the fed hours can change daily.

How do I get enough calories in if I fast?
For those looking to decrease calorie intake for weight loss, ADF is the best option. For those looking to improve other health areas without worry about weight, TRF is a better option. During your fed hours, eat normal. The point is to give your body rest from eating, not eat less overall (unless you’re trying to). Work on eating balanced, dense meals with added nuts, seeds, grains and fats to get the calories you need.

Won’t it mess with my hormones (female)?
Maybe. Research is mixed here, but mostly shows that if you are eating a nutrient dense diet rich in complex carbohydrate on your fed days and not doing extended fasts, you will see benefits to the regulation and balancing of your female hormones. TRF is the best option for this goal. Keep in mind that it isn’t a magic / instant fix. If you are going into IF with messed up hormones, you need to give it time. See note below*

*Bottom Line

IF is a style that can work for many of us to improve health outcomes, whether its weight loss or prevention. Like any diet/ lifestyle change, there is a period of struggle related to the change, so monitor your body and ease into it. Start by doing 8 hours of fasting for 5days/wk then 10 hours the next week and 12 after that. If ADF is your goal, start with one 1/2 day fast a week, then one full day, then 2 days. Throughout your fasting process, always look to evaluate the metrics you are hoping to change (blood panel, hormones, stress, mood, power, speed, weight, etc).

Those taking many medications, pregnant, or struggling with eating disorders should avoid IF.

I always suggest that a program of dietary change be implemented with the help of a professional. To get the most out of your fast, book a session with me.

Running Strength

Running Strength

Post Run Meal

Post Run Meal