Your First Week on the Keto Diet: What to Do and What to Expect

This LEGO is angry about how he feels on the first week of Keto. We'll give him some tips to calm him down a little.

So you’re going to try the Keto Diet…now what?

You read this step-by-step plan! 

We help our coaching clients complete life overhauls, including starting low-carb diets, and today we’ll share with you the tricks of the trade.


After today, you’ll know exactly what to do to begin the Keto Diet. 

Real quick: if you are just starting your low-carb journey and want to learn what it’s all about, make sure you grab our MASSIVE Beginner’s Guide to the Keto Diet. It’ll teach you everything you need to begin Keto. You can grab it for free when you join the Rebellion (that’s us!) by enlisting below: 

What to Do Your First Week of the Keto Diet

Here’s exactly what you should do when you decide to try the Keto Diet.

#1) Take before photos and measurements:

  • Take front and profile photos of yourself. You don’t need to look at them or share them anywhere, but I PROMISE you’re going to want those. 
  • Record your weight and take any measurements you want.

Write this stuff down and keep it secret, keep it safe.

You don't have to share your photos and measurements, just like you don't have to share knowledge of the one ring.

These tips are exactly how are coaching clients track their fitness progress. You’re going to want to see how your body responds to a low-carb diet, and pictures coupled with measurements will help tell the story.

#2) Calculate your calories and macros:

A: Determine your total calorie intake goal. Calculate your “basal metabolic rate(how many calories you burn per day). I am 6’0″, 185 lbs, and my BMR is roughly 1814 calories. I am active, so I’m multiplying this number by 1.375 to get to my active daily calorie burn: 2814 – let’s make this an even 2800.

B: Take 5% of that number for your total amount of carbs. Divide by 4 (there are 4 calories per gram of carbohydrate).

I have 140 calories for carbs, divided by 4, equals 35 grams of carbs. That’s a nice round number so we’ll stick to that.[1]  

C: Next, calculate your protein requirements. If you are active, Target 0.8-1.2 g of protein per pound of weight. This is a simplified version of a complex calculation you can do, which is dependent on your lean body mass, how active you are, etc. You can multiply this by 4 to see how many calories total that would be.

I’ll again keep it simple and make it 180g for me. 180 x 4 = 720 cal. Which means so far I have used up roughly 860 calories of my 2800 calories, so I have 1940 calories remaining.

D: What’s leftover? Fat! There are 9 calories per gram of fat. So divide your remaining calorie count by 9 to see how many grams of fat you should eat per day.

In my example, I have 1940 calories remaining, divided by 9, which means I need to consume about 215 g of fats per day. Yup. This is a lot of fat.

Yep, you're going to have to eat a lot of fat (like cheese) on Keto. Time to act like Jerry here!.

E: Put it all together, write it down, start tracking your food, sucka! I’m sorry for calling you a sucka, I didn’t mean it. In my example, I’m looking at 215g of fat, 180g of protein, and 35g of carbs. Want help figuring out what foods will help you reach these specific macros? Read our guide “Start Eating Healthy Without Being Miserable” for meal ideas including macro breakdowns. 

#3) Go shopping for your Keto foods, and order your Keto snacks on Amazon. Check out The Beginner’s Guide to the Keto Diet for loads of ideas on recipes for the Keto Diet.

#4) Consider picking up an electrolyte supplement to help you through the first few days/weeks of grogginess/lethargy as you move through the Keto flu stage. You can also look into the urine test strips or blood testers – I find that knowing I’m in ketosis, it helps keep me accountable and motivated that all these changes are actually working!

#5) Eat out frequently and enjoy fast food? Check out our guide for the best low-carb options on the go. Having a plan on what to eat before you arrive will help you stay on track.

#6) Tell somebody. The biggest problem with Keto is simply sticking with it. If you have roommates or a significant other or friends you can speak to and get them on your team to support you. In fact, send them this article and recruit them to try it with you! That way they’re not enabling you to slip up, they’re keeping you accountable!

Don’t have anybody to tell? Our NF Academy has the most supportive community on the internet.

#7) Consider kickstarting your week with a fast. This is going to be a mental and physiological challenge. Consider skipping breakfast tomorrow – it’s one less meal you have to prepare, one less chance to knock yourself out of ketosis, and can help kickstart the Keto-adapted phase!

#8) Throughout the week: Focus on big wins, allow yourself to be miserable – Keto flu is REAL, giving up carbs is hard, and your body is going to hate you:

  • Drink plenty of water and supplement with electrolytes if you find yourself getting headaches. Add more salt to your food and focus on consuming more leafy greens to get that electrolyte balance back in place. 
  • Lean on your support group. Talk to others who have been where you are, ask questions, share your struggles!
  • Eat snacks when you are miserable. I’d rather you eat some snacks and slightly overeat on your calories than be so miserable that you give up.
  • Track your adherence. Use MyFitnessPal (though not their recommended macronutrient breakdown!) to track every meal you eat – this is very important in the first week as you’re educating yourself dramatically.
  • Do your best – you might slip up with one meal or realize you accidentally ate carbs. This is not the end of the world. Forgive yourself, learn the lesson, and get right back at it with the next meal.

#9) Keep going, or adjust. Depending on your body, your environment, the way you used to eat, and your physiology, this first week will either be “hey, not too bad” or “never again.”

If you hated your first week of Keto, that's okay! You learned something, which is important!

Either way, you’ll learn something. 

I do hope you push through this for a full 30 days and see how your body responds once it’s out of the Keto Flu stage! Let’s chat about what to do then.

What to Do After You Try the Keto Diet

At the end of your first month on Keto, take more photos and measurements and compare them to your starting “before” stats. 

  • Do you feel better? 
  • Do you look better? 
  • Did you enjoy the process?
  • Was the process sustainable for you? 


Great! Keep going. 

Hated it?

Great! You found a method that doesn’t work for you.

This Mutant knows it's no big deal if you don't enjoy the Keto Diet. Try something else!

Simply adjust and create your own strategy.

The important thing is to be willing to experiment and to find what works best for you.

Want a little more help getting going? You seem like a nice person, so I have three great options for you:

#1) If you want step-by-step guidance and a coach to keep you accountable, check out our killer 1-on-1 coaching program:

#2) Good at following instructions? Check out our self-paced online course, the Nerd Fitness Academy.

The Academy has 20+ workouts for both bodyweight or weight training, a benchmark test to determine your starting workout, HD demonstrations of every movement, boss battles, meal plans, a questing system, and a supportive community.

3) Join the Rebellion! We need good people like you in our community, the Nerd Fitness Rebellion. 

Sign up in the box below to enlist and get The Beginner’s Guide to the Keto Diet. It’s all you need to start your low-carb journey.

Enough of what I have to say. Now I want to hear from you!

Are you currently trying the Keto Diet?

Are you planning on starting your first week?

Any tips or tricks you have for the first seven days of Keto?

Let us know in the comments!

For the Rebellion,


PS: Make sure you check out the rest of our guides on following a low-carb diet:


Photo Source: put up your hands. 

GIF Source: Gandalf, Mouse, Nick Miller, NBD.

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