Intermittent Fasting: A Getting Started Guide

Have you read Intermittent Fasting: An Origin Story yet? I'd recommend skimming that post before diving into this one.


It's happened to all of us: you slept through your alarm, jumped out of bed in a frenzy, and rushed off to {insert important commitment here}. Forced to skip breakfast, you had to wait until lunchtime to eat your first meal of the day. Not only did you have a hectic start to your day but you also, unknowingly, practiced intermittent fasting.

Intermittent fasting is a pattern of eating in which one alternates between periods of feeding and fasting. IF is based on the fact that your body can be in one of two states: fasted or fed. You're in the "fed" state when you have recently had a meal and your body is digesting and converting the food to energy. Your body reaches a "fasted" state once the energy derived from that food has been depleted, typically about 10-12 hours after your last meal.

Frequent fasting can improve your health in myriad ways, by promoting weight loss, longevity, improved brain function, and much more. Sounds awesome, right? Most people get on board with the benefits of intermittent fasting but tend to jump ship when they realize they actually have to fast to reap those benefits. However, with a concrete plan, transitioning to an IF pattern of eating can be incredibly easy.

Below are the 5 questions that comprise my Intermittent Fasting Getting Started Guide. These are the questions I answered to develop a simple strategy for implementing IF in my own life, and I have revisited them throughout my intermittent fasting journey. If you have ever wanted to try intermittent fasting, answering these 5 questions will help you get started. Be honest with yourself, be aware of how you feel, and be open to experimenting. I promise you won't regret it.


1. How many calories do you need to maintain your weight?

Start by calculating your maintenance calories, which is the amount of calories you would need to consume to maintain your current weight. This number is a great starting point, and I suggest anyone trying IF for the first time should start out by eating at maintenance. Once you feel comfortable with IF and the way you practice it, you can adjust based on your goals, which leads to the next question....

2. What are your health goals?

Everybody has different health goals and it is important to identify and vocalize your own goals. Below I address the three main categories of health goals. You will want to identify which category - or combination of categories - you fall in and adjust your caloric intake accordingly. 

  • Maintain current weight and physique. This one's easy: Eat at maintenance and maintain your current activity level.
  • Lose weight (decrease body fat). Losing weight is a matter of calories in, calories out and can be achieved either by reducing calorie consumption or increasing calorie burn. If you don't want to exercise more than you currently do, take 100-300 calories off your maintenance amount, depending on the intensity of your weight loss goals. If you do not want to eat less than your maintenance calories, aim to walk 10,000-15,000 steps per day.
  • Gain weight (increase muscle mass). If you want to build more muscle, you'll have to lift more weight or increase the frequency of similar strength exercises. Eating 100-200 calories above maintenance can speed up the bulking process but can also lead to fat gain.

3. How much protein do you need?

Most health professionals will recommend 0.4-0.8 grams of protein per pound of body weight. If you weigh 150 pounds, then you will want to consume somewhere between 60 and 120 grams of protein. Protein is necessary for proper muscle growth, bone strength, brain function, and heart health, so it is crucial that your daily protein intake lands in this range.

4. When are you going to eat?

When you eat each day is based on your own personal practice of intermittent fasting. There are a variety of ways to practice IF, as I discussed in my first IF post. The key difference between the various methods is the length of the feeding window - the amount of time you take to consume all your calories for the day. As long as you account for a fasting window of at least 12 hours, you can eat any time of day. The best feeding window for you is the one that fits your schedule, personal preferences, and makes you the happiest. 

5. What are you going to eat?

This question is the most fun to answer! Planning out and preparing meals is so rewarding when you know how to feed yourself optimally. When deciding what you will eat, focus first on protein-rich foods and some fruit and veggies. After that, eat the foods you love to hit your calories for the day. The guidelines around what to eat are simple and non-restrictive.


Below, I have given my own answers to these questions, in the hopes that they will help guide you towards your own IF practice.

1. How many calories do you need to maintain your weight?

According to the calculator, my estimated daily maintenance level is 1831 calories. I weigh 122 pounds, I am 5'6" tall, I am 22 years old, I am a female, and I am lightly active, which means I perform moderate exercise but have a sedentary job.

2. What are your health goals?

My current health goals are a combination of the categories outlined above. I want to maintain my current weight but would like to "tone up" by increasing muscle and decreasing fat. I walk at least 10,000 steps a day and lift weights 3 days a week. Since I have increased my activity level to reach these goals, I have not altered my caloric intake. Therefore, I eat right at maintenance every day.

3. How much protein do you need?

Based on my body weight, I should be eating between 49 and 98 grams of protein each day. Since my current goal is to build muscle and lose fat, I aim for the upper end of that range, usually consuming between 85 and 95 grams of protein. Many people fear the expense of a protein-rich diet but you don't have to eat organic, grass-fed beef every day to hit your protein goal. Beans, dairy, eggs, canned fish, nuts and nut butter are excellent cost-effective sources of protein.

4. When are you going to eat?

As mentioned above, when you eat each day depends on the way you practice IF. My practice falls somewhere between the Fast-5 Diet and the Warrior Diet. The Fast-5 Diet involves eating all your calories for the day within 5 consecutive hours, whereas the Warrior Diet involves consuming all your calories for the day in one massive meal. Since my feeding window is pretty small, I like to eat late enough in the day so that I don't go to bed hungry but not so late that I go to bed before my food has fully digested. Therefore, I usually break fast around 4:00-4:30 PM (as I am leaving work) and finish eating around 7:00-7:30 PM. This could change depending on the day and what I am doing after work, but that is my typical feeding window.

5. What are you going to eat?

I plan out all my meals in the Evernote app. 10/10 would recommend!

I absolutely LOVE planning out my meals. I feel tremendous eating the epic entrees I prepare for myself after fasting all day. Each night, I plan out what I will eat the next day and, in doing so, I guarantee that tremendous feeling.

My beautiful "dinner"


More resources for getting started:

If you read Intermittent Fasting: An Origin Story, you'll know that my brother introduced me to intermittent fasting. He has excellent tips on fasting and overall wellness, which he documents on his Instagram

Greg O'Gallagher is known across YouTube and Instagram for popularizing intermittent fasting. Ignore the fact that he's Canadian and focus on the fact that he knows his shit.

NerdFitness has a great beginner's guide. Highly recommended for biology nerds!

James Clear's guide for beginners is pretty awesome too.


Have you tried intermittent fasting? I'd love to hear about your experience with it in the comments below! You can reach out to me here for any comments/questions you have.