food journal

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A lot of people struggle to manage their weight [1]. The reason for this can be boiled down to one thing. Weight management is simple, but not easy.

Your weight is regulated by the principle of calorie control. Consume more calories than you burn each day and you will gain fat. Consume fewer calories than you burn and you will lose fat. That’s the core of weight control.

There are dozens of factors that will affect short term water-weight fluctuations, body composition (how much muscle you have compared to how much fat you have), and even your appetite and energy levels.

There are even small differences in how many calories two people of similar age, weight and height might burn based on the speed of their metabolism.

None of those things make Calories in vs Calories Out (CICO) [2] invalid. They simply make it hard to manage. Keeping a food journal is one thing that can make weight loss feel easier.

Top 4 Reasons to Keep a Food Journal

a woman writes her daily food log in her journal

Food journals serve a few purposes [3]. Firstly, they help you to keep track of what you are eating so that you can tell whether you’re meeting your micronutrient and macronutrient goals.

Secondly, they make you think about what you’re eating. They can flag up issues, such as “it’s 2 PM and I’ve eaten most of my calories for the day”, or “I’ve eaten a ton of carbohydrates but no healthy fats” or “I haven’t consumed much in the way of vegetables today”.

They can also make you stop and think. If you’re someone who snacks mindlessly the logging the third 50 calorie cookie for the day might make you stop and wonder whether you actually want to waste calories on it.

1. Food Journals as a Psychological Aid

If you can get into the habit of writing down what you eat, or logging what you eat in an app such as MyFitnessPal or Cronometer (both free to download and use for iOS and Android phones, as well as having website versions), then you may find that simply knowing that you need to take a few seconds to log what you are eating will help you to stop and think about whether you want to eat [4].

A lot of people spend hundreds of calories per day on mindless snacking. That’s next to nothing for an adult male who is very active, but it’s a huge portion of the daily calorie intake for a small female with a desk job.

2. Learn About Your Eating Habits

Food journals can lay bare the food that you’re eating.

If you’re one of those people who “eats next to nothing but cannot lose weight”, then logging your food faithfully for a few weeks could help you to understand where the calories are coming from [5].

a woman eating pizza

That creamy Starbucks with syrup could be 600 calories. Add a chocolate bar at lunchtime and that’s 850 calories gone before you start thinking about “real food”, so even if you have a small breakfast, a salad for lunch and soup for your evening meal you could be over your daily calorie allowance.

You’ll feel deprived and “starved” because nothing you’ve eaten is particularly filling, but you’re still taking in too many calories.

It could be that having a smaller Starbucks with skimmed milk and sugar-free syrup could free up hundreds of calories for ‘real food’, and then you’ll feel like you’re eating more while staying within your calorie goal.

Another nice side effect of logging your food is that you can keep track of how you feel as well. Some people find that eating a large breakfast stops them snacking throughout the day.

Others can skip breakfast and have lots of energy, then don’t feel hungry until late afternoon.

You may find that you feel best if you eat lots of whole grains, or that you feel hungry almost immediately if you eat potato chips or white bread for a large part of a meal.

Important Note: There is No One Single Diet That Works for Everyone

All diets, whether Atkins, Keto, Paleo, Intuitive Eating, Intermittent Fasting, South Beach, Weight Watchers (now WW), and other popular brand named diets work based on CICO.

Even if they say that you don’t need to count calories, the end result is the same. By either encouraging you to avoid certain foods, or encouraging you to focus on eating a certain type of food, the theory is that you will eat fewer calories and lose weight. What the brands are selling is a way to lose weight without feeling deprived.

If you were locked in a room and fed exactly the right amount of micronutrients and calories for your goal weight, you would eventually reach that weight. You might be miserable and feel hungry all the time, but you would get there.

Of course, who wants to be forced to eat exactly a certain amount of calories if they’re going to feel terrible as a result?

3. Food Journals Put You In Control

a person writes in their diary

The beauty of food journals is that they put you in control [6]. When you use a food journal no food has to be off limits. You can eat pizza on a Saturday night if you want.

You can have chocolate or ice cream if you want.

You know that the chocolate bar was 250 calories, that serving of ice cream was 400, and the pizza was 1,100. It’s up to you how you fit them into your daily calories.

You can choose to skip breakfast and have a big lunch with friends.

You can exercise throughout the week and then know that since you worked out three times that week you aren’t going to lose a lot of progress by going 500 calories over your goal once that week. You can eat low calorie foods most days, but then have some popcorn at the cinema.

If you go over during the holidays, you will know how much you went over by, and not worry too much about it. Because you know that your “over-indulgence” was only slight, you won’t feel like restricting your calorie intake massively to compensate so you will avoid that binge / restrict cycle that a lot of people fall victim to.

4. Food Journals Take Away The Stress of Dieting

If you are currently overweight, it’s likely that you didn’t get there overnight [7]. It probably took years to gain the weight, and it will take months or years to lose it. A reasonable goal is 1lb a week for people who are overweight, and perhaps 2lb per week if you are obese. That means a calorie deficit of 500-1000 calories per day.

Tools such as MyFitnessPal will give you an idea of how many calories you should eat per day to reach your weight loss goal.

a happy couple makes dinner together

Your calorie allowance will change as your weight does, which is why it is important to re-calculate your daily energy expenditure and calorie allowance every time you lose 10 lbs or so.

You should weigh yourself once a week, at the same time of day, wearing similar clothing (so weigh yourself naked at home when you get up in the morning, or weigh yourself on Friday on the way home from work, wearing your usual work clothes but no coat… the important thing is to be consistent) [8].

By weighing yourself in similar conditions weekly, you will avoid a lot of the stress that comes with day to day fluctuations based on water weight, what you ate last night, etc.

If you are female you may still have to contend with hormonal weight fluctuations but they should be minimal.

If you are keeping a food journal then you will know that you have been sticking to your diet, and if you don’t see any change in your weight for a few weeks in a row you can adjust your calorie allowance down by another 250 calories and see how that goes. If you weigh, measure and log everything that you eat and drink (yes, liquid calories count too) then you will know whether or not you are on track.

Food journals work alongside other diets. They can help you log whether you’re in ketosis, they can guide your macronutrient intake for other diets, and remind you how many calories you need to eat in your Intermittent Fasting window.


Logging your food intake need not take over your life. You can work out some stock ‘meals’ and know that you have room for your usual bowl of oats, a meal deal from the local convenience store, and your favorite casserole when you get home, but that you should say “no thanks” to that donut in the break room.

There you go.

That’s all the thinking about food that you have to do that day. Use food journaling to help you keep your head clear and to understand what works best for your body. Don’t become a slave to calories. Don’t stress too much about what you can and cannot eat. Remember that knowledge is power, and that weight loss is about a series of small choices.

No one decision is the end of the world, it’s patterns that matter.


  1. Why do I find it so hard to lose weight? The Blood Sugar Diet. Retrieved from
  2. Alina Petre, MS, RD, Does ‘Calories in vs. Calories out’ Really Matter?, HealthLine. Retrieved from
  3. Katherine D. McManus, MS, RD, LDN, Why keep a food diary? Harvard Medical School. Retrieved from
  4. Marcia Herrin Ed.D., M.P.H., Food Journals, Food Records, and Self-Monitoring: A new take on a tried and true technique, Psychology Today. Retrieved from
  5. Surprising benefits of keeping a food journal, Qardio. Retrieved from
  6. Nutrition: Keeping a Food Diary, FamilyDoctor. Retrieved from
  7. Consumers Union of United States, Extra weight can sneak up on you, but there are ways to avoid putting on pounds, Washington Post. Retrieved from
  8. American Hearth Association News, The pros and cons of weighing yourself every day, Retrieved from

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