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Keeping a Food Diary

What is a food diary?

A food diary is a record of the food you eat each day. This can help you in several ways:

  • It can help identify problem foods if you have a food allergy or digestive problem, such as reflux or irritable bowel syndrome.
  • It can help you and your healthcare provider learn what you are eating and how balanced and healthy your diet is.
  • If you are trying to lose weight, tracking your eating habits can help you create a healthy plan for weight loss. People who lose weight and keep it off often keep food diaries even after they reach their weight goals.

Whether you are using your food diary to identify food allergy or intolerance or as a tool to help you lose weight and eat better, don't change your eating habits for the first few days. Knowing what you normally eat is the only way to know what kinds of changes to make. Write down or record everything you eat. Be honest and thorough.

What information should I track?

To find foods that may be causing allergic or digestive symptoms, track:

  • All the foods that you eat (be specific about the food and any added toppings, such as cheese, mayonnaise, and sauces)
  • How much (portion sizes) of each food you eat
  • The times of day when you eat
  • Any symptoms you have after eating a food, such as rash, headache, diarrhea, or a stuffy nose
  • The time symptoms started and how long they lasted.

If you are using the food diary to improve your diet and help you lose weight, track:

  • All the foods that you eat (be specific about the food and any added toppings, such as cheese, mayonnaise, and sauces)
  • How much (portion sizes) of each food
  • The times of day when you eat
  • Where you eat
  • Who you eat with
  • What you are doing while you eat, such as watching TV
  • Your thoughts and feelings before and after eating. For example, sometimes you may eat because you are bored, stressed, or depressed and not because you are hungry. Once you are aware of why you eat and when, it can be easier to see what you may need to change. For instance, if stress causes you to overeat, exercising or doing something else can be a healthier way to deal with the stress.

A food diary can be as simple as a notebook or using a computer program or phone app. Keep your food diary with you and try to note foods as you eat them. If you wait until late in the day, you may be more likely to forget some foods or how much of them you ate.

How do I know what a portion size is?

For portion sizes, use measurements such as inches, cups, and ounces for the amounts of foods that you eat. For example, you might record that you ate a 2 x 2 inch piece of cornbread, 1 cup of oatmeal, a 12-ounce soda, or a 3-ounce chicken patty.

Here are some simple ways to measure portion sizes:

  • 1 cup of starchy food, such as mashed potatoes or pasta, is about as big as a closed fist
  • 1 serving of a fresh round fruit is about the size of a tennis ball.
  • 3 ounces of cooked meat is the size of a deck of cards.
  • 1 ounce of cheese is about the size of your thumb.
  • 1 teaspoon of margarine or mayonnaise is the size of the tip of your thumb.

You can also use food labels to learn typical serving sizes, the amounts of calories in each serving, and other nutrient content. If you have diabetes, talk to a dietitian or your provider about creating a food plan to keep your blood sugar in a safe range. Your food diary can help you stay on track.

How can I get more information?

You can get more information from:

Developed by RelayHealth.
Adult Advisor 2015.1 published by RelayHealth.
Last modified: 2015-01-02
Last reviewed: 2015-01-02
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.
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