Food Log shows what your food means for you and for the planet. Type what you ate, for example 150g yoghurt, choose the right product, and you immediately see the nutrition and three environmental figures: greenhouse gas, land use and irrigation water. This page explains where those figures come from and how to read them.
Every environmental figure covers the whole life of a food, up to the moment you eat it: farming, processing, packaging, transport, the shop and cooking at home. The figure is scaled to the amount you entered. Cooking is already included, so nothing is added for it.
Where your data is
In this browser, on this device. Your log, your weight and the foods you added yourself are stored here and nowhere else. There is no account and nothing to sign in to.
The calculations do happen on a server, because they need 1.4 MB of reference tables from RIVM, NEVO, HYDE and FAOSTAT. Each screen sends only the part of your log it needs: one day for the Day tab, your whole log for the charts. The server works out the answer, sends it back and throws its copy away at once. Nothing is stored there, and one request cannot be linked to the next.
This means that you hold the only copy. If you clear your site data, use a private window or reset your phone, your log is gone. The app asks your browser to treat your data as worth keeping, so it is not removed when the device runs low on space. Not every browser agrees to that, and no browser protects data you delete yourself. On the Trends tab, under Your data, you can see what your browser answered and download a backup. A backup is also how you move your log to another device.
You can also download the app as a single file and use it on your own computer, with the ⤓ button at the top of the screen. Your log then still stays in your browser, but the calculations happen on your own computer as well.
What each number means
Greenhouse gas
How much a food adds to global warming over its whole life, in kg CO₂-equivalent per kg. Small amounts are shown in grams. This includes carbon dioxide, methane and nitrous oxide.
Source: RIVM 2024, calculated with the ReCiPe 2016 (H) midpoint method. The formal name of the method is given so you can trace every figure back to its source.
Land use
The area of land needed to produce a food, multiplied by the time that land is in use, in m²·year per kg.
Source: RIVM 2024, ReCiPe 2016 (H) midpoint.
Irrigation water
Only blue water: fresh water taken from rivers, lakes and groundwater to irrigate crops, in litres per kg (stored as m³). Rainwater and water weighted by scarcity are never added to it, because they measure something else.
Source: RIVM 2024, ReCiPe 2016 (H) midpoint.
Nutrition
Energy, protein, fat, carbohydrate and fibre, per 100 g of the part you actually eat. Peel, bones and other inedible parts are already left out. The figures are scaled to the amount you entered.
Source: NEVO 2025/9.0.
Custom foods
Can't find a food, such as a branded product or a dish you cooked yourself? Add it by hand. You fill in the nutrition per 100 g and, if you have real figures, the environmental impact per kg. You can change it later with the ✎ button next to an item or a search result. A change applies to every item that already uses that food.
Everything you fill in yourself is saved with the method user-entered and carries that label wherever it appears, so it is never confused with RIVM or NEVO data. Leave a field empty if you don't have a figure. The app then records that there is no data. It never estimates a value and never copies one from a similar food.
Your own sources. For environmental figures you can note where they came from, such as a supplier's product sheet, a package or a published study. That source is saved and shown next to the figure. If you leave it empty, the figure is filed under User entered. Naming a source does not turn your figure into reference data. The method stays user-entered, because the app cannot check what you typed or whether it uses the same scope and units as the rest of the data. The source tells you where the figure came from. The method tells you that nobody has checked it. For the same reason you cannot file your own figures under the name of a reference source such as RIVM.
If you change the source of a food that already has figures, those figures move to the new source. They are not copied, so a figure never ends up with two values from two sources.
Source: you. Environmental figures you fill in should cover the same scope as the rest of the app: the whole life of the food up to your plate, including cooking.
Why environmental figures are usually a lower bound
Only about one in five foods in this app has environmental figures. RIVM covers around 490 of the roughly 2,300 foods in NEVO. Nutrition is almost complete, but the environmental figures are not.
The environmental figure for a day only adds up the foods that have figures. Say you enter 1 kg of spareribs (no figures) and 300 g of lentils (with figures). The day then shows only the lentils: a small number for a day that was mostly pork. Such a figure is a lower bound and not a total. A food without figures can only make the real number higher, never lower.
That is why the app puts ≥ in front of a figure when data is missing, shows how much of the weight was counted, and draws such a day as an open dot in the charts. Otherwise a gap in the data would look exactly like a day with a low impact. Want more complete figures? Choose foods that RIVM covers, or fill in your own figures for a custom food.
Your average, and reference diets
Your average on the Trends tab is your own average per day you filled in, over the period shown. Each figure only counts the days that have data for it. A day on which nothing you ate had environmental figures is skipped, so it does not count as zero. That is why each figure shows how many days it is based on.
If one of those days is a lower bound, the average is one too, and it says so. The app also gives a separate figure over only the days on which everything you ate had environmental figures. Only that figure can fairly be compared with a reference diet. If there is no such day yet, the app tells you so, instead of showing a comparison it cannot back up.
On the greenhouse gas and energy charts of the Trends tab you can switch on reference lines for complete diets. Use them as a rough guide. Each line comes from a different study, with a different method than your own log, so they are indicative and not an exact comparison. Land use and irrigation water get no line, because there is no reliable figure per diet for them.
The figures in this list carry ≈ because each one is a single published average, without a range.
- Average Dutch diet: ≈4.0 kg CO₂-eq per day (≈3.7 for women, 4.8 for men) and ≈2100 kcal per day. From a Dutch study of the greenhouse gas emissions of diets, linked to RIVM. Its method is the closest to that of your own data.
- Planetary diet: ≈2.5 kg CO₂-eq per day and ≈2500 kcal per day. From the 2019 report of the EAT-Lancet Commission. It describes a diet that is healthy and that the planet can sustain in the long run. Few people eat this way today.
- Average world diet: ≈4.7 kg CO₂-eq per day and ≈2500 kcal per day. Based on the emissions of the global food system. This is a rough figure that counts more broadly than your own data.
The World tab
The World tab compares how much land your food needs with what the average person in the Netherlands needs. It then shows what the world's land would look like if everyone's food needed land in the same way. It is a comparison. The tab does not measure how much land you use yourself. The figures behind it describe Dutch farming, and land use does not carry over directly from one country to another. You can read what it is built on, and where it becomes less reliable, on the page about the World tab.
Below the map, the tab does the same for greenhouse gases and adds them up over a hundred years. You see what the world's food emits now as the population grows, what that would be if everyone ate like you, and what the land then does with carbon. Land that goes back to nature first takes up a lot of carbon, and after that a little more every year. That last part is drawn twice, because a hectare of cropland holds more than twice as much carbon as a hectare of grazing land, and the kind of land a diet frees up changes the outcome. The chart counts tonnes of greenhouse gas. It does not calculate degrees of warming, because that would need a climate model.
Data sources
- Environmental impact: RIVM Database Milieubelasting Voedingsmiddelen 2024. Licence CC BY 4.0.
- Nutrition: NEVO, the Dutch Food Composition Database, version 2025/9.0 (RIVM), per 100 g edible part. Licence CC BY 4.0.
- Land on Earth: HYDE 3.5 (PBL and Utrecht University), ESA CCI bare areas 2022, Natural Earth glaciated areas, and RIVM letter report 2024-0101 for the Dutch average per person. More on the page about the World tab.
- World emissions and population: FAOSTAT Emissions Totals (UN FAO), UN World Population Prospects 2024, Hayek et al. 2021 for the carbon that land holds, and the Global Carbon Budget 2024 for how much carbon land absorbs. Licences CC BY-NC-SA 3.0 IGO, CC BY 3.0 IGO and CC BY 4.0.
A limitation RIVM points out itself
RIVM's figures have not been checked by independent experts. That check, called a critical review, is what the ISO 14040 standard for life cycle assessment requires before results are published for public comparison. RIVM therefore states that the data is not suitable for publicly comparing individual foods. This app is meant for personal use. Please do not use it to rank foods or to compare them in public.
Some composite foods, such as porridge or mousse, have no measurement of their own. Their impact is then composed from the RIVM figures of their ingredients, and the method name ends in -composed wherever it appears. These are derived estimates. They tend to come out a little low, because every preparation step except combining the ingredients is missing.
Uncertainty ranges have not been loaded yet, so environmental figures are shown as central estimates. The ranges will appear once that data is added. Foods without environmental figures show no data, never zero. Each day states how much of the weight you entered has no environmental figures, and every total that rests on incomplete data is marked with ≥. Read more under why environmental figures are usually a lower bound.
Ready to start? Go back to the app and enter what you ate today.