How to Keep a Food Journal You Will Actually Read Back

A food journal you will read back has five columns: time, food with its state, grams, calories and one line of context. Fill it in close to eating, and sit down with it once a week. In a 24-week trial, those who lost at least 5% of their weight opened their journal 2.4 times a day, against 1.6 for the rest. Among those still logging at month 6, time spent didn’t differ between the groups. Frequency did.

What goes in a food journal entry?

Five things go in: when, what, how much, how many calories and where you were. Food journal, food diary and food log all mean the same record. I say “journal” because it invites a note, and the note is what makes a page worth reading later.

Each “what” needs its state. Each “how much” needs grams. Take oatmeal. Rolled oats, dry have 379 kcal per 100 g, so 40 g is 152 kcal. A cup of dry regular oats weighs 81 g and has 307 kcal, twice as much. If your page says “oatmeal” with no state and no weight, you can’t tell which one you ate. In three weeks you won’t be able to tell either. The scale gets quick with practice, and how to weigh food for macros covers taring the bowl and raw versus cooked.

Calories can wait, because grams and a food name are enough to work them out. A note can be as short as “at my desk” or “cooked in batch”. If you want protein, carbs and fat per row as well, how to track macros shows which columns to add.

Copy this header into whatever you use, and add a weight line at the bottom only if you want one. Keep it plain.

Time	Food and state	Grams	kcal	Note

Tonight, write today’s three biggest meals into those five columns, even from memory, and mark guesses with a tilde.

When should I write it down?

Right after you eat, in small pieces. In that trial, opening the journal several times a day went with losing more. The habit that fails first for me is the single sit-down at night, because by then I’m guessing. One lab study followed 10 adults who reported eating under 1,200 kcal a day yet weren’t losing weight. Over 14 days they underreported their real intake by 47% on average. A group that small and selected can’t describe everyone, but it shows how far a self-report can sit from the measurement.

It takes time at first. In that trial, people spent 23.2 minutes a day in month 1, falling to 14.6 minutes in month 6. The first month feels slow because it is.

I keep one rule. If I can’t write it now, I photograph the plate and fill in the grams at the next break. The photo is a note to myself, not the entry.

What does a filled page look like?

Here is one sample day, built from USDA records. The grams are what I’d weigh, and the calories are per 100 g × grams ÷ 100.

Time	Food and state	Grams	kcal	Note
07:30	Rolled oats, dry	40	152	home, before work
07:30	Banana, raw	115	101
10:30	Greek yogurt, plain, nonfat	156	95	at my desk
12:45	Chicken breast, braised	150	249	lunch with colleagues
12:45	Brown rice, cooked	202	248
12:45	Broccoli, raw	152	49
12:45	Olive oil	13.5	119	cooked in batch
16:00	Almonds, raw	28	163
19:30	Eggs, whole, large	100.6	148
19:30	Lentils, boiled	198	230
22:00	Peanut butter, chunk style	32	188	straight from the jar
Total			1,742

This page isn’t a target. It’s a readable day, and the total is nothing more than the column added up. If you buy the same dozen foods each week, a calorie counting grocery list hands you their unit weights, and the grams column fills faster.

How do I read a food journal back?

Once a week, ask the pages three questions, in this order, and jot the answers at the bottom of the last page. Where did most of the food land? Which entries have no grams? Which foods showed up three or more times?

Run them on the sample day, where lunch is chicken, rice, broccoli and olive oil. Split by time, the 1,742 kcal come to 348 kcal before noon, 828 kcal from noon to 5 p.m. and 566 kcal after 5 p.m. Lunch alone is 665 kcal, 38% of the day. That’s the big block. Inside that lunch, the olive oil is 119 kcal, 18% of the meal from one tablespoon. Without a grams column the oil stays invisible, because nothing in a food’s name says how much of it went in the pan. The peanut butter at 22:00 is 188 kcal, and the note says it came straight from the jar.

Take one change from those answers. I’d pick the oil: weigh it for a week and see if the number holds. A week that turns up nothing to change is a good result too.

Put the read-back in your calendar, because pages you never reread only pile up.

To set a week of totals against a figure for your own body and activity, use the calorie calculator. It never goes below 1,200 calories for women or 1,500 for men.

Paper, notes app or a tracking app?

The one you will still open in month two. A 6-month pilot gave 128 adults a phone app, a website or a paper diary to record food. App users logged on a mean of 92 days, diary users on 29. By month six, 93% of the app group was still in the trial, against 53% of the diary group. Weight moved -4.6 kg with the app and -2.9 kg with the diary. Small pilot, one researcher-built app: it can’t rank products.

Paper has real strengths: nothing to open, nothing to update. Its weak spots are the arithmetic and the lookups, and a notes app sits in between. If your pages stay half-empty after two weeks, change the method before you blame yourself. The approach in how to track calories, weighing the few foods that carry most of the calories, keeps the pages short enough to survive a busy week.

When should I stop?

When it stops informing you and starts pressuring you. A survey of 493 college students found that calorie-tracker users reported more eating concern and dietary restraint, though it couldn’t show which came first. If writing food down makes you anxious, put the journal away. If you are pregnant, ill or under 18, check with your doctor before you start.

Once a page makes you feel graded, it has stopped doing its job, so close it.

If counting calories has started to feel hard to stop, or eating feels out of control, talk to someone: ANAD in the US (1-888-375-7767), Beat in England (0808 801 0677), NEDIC in Canada (1-866-633-4220) or the Butterfly Foundation in Australia (1800 33 4673). If you’re in danger right now, call your local emergency number. Other UK numbers and crisis lines are on our crisis support page.