Flexitarian
What it is
Mostly plants, meat sometimes, and no rule about how often "sometimes" is. The word describes how a great many people already eat — the vegetable dishes and bean days of most traditional kitchens, with meat at the weekend — and it is on this site because people ask about it, not because it is a diet in the sense the other pages use. It has no definition, and a pattern without a definition cannot be tested.
How it works in practice
Vegetables, legumes, grains, eggs and dairy most of the time; meat and fish when wanted. In a Bulgarian kitchen this is Tuesday's lentils, Thursday's stuffed peppers and Sunday's roast, which is the point: for many households it is not a change but a name for what they do.
What the evidence shows
For weight, nothing that this site can cite. There is no defined flexitarian intervention to randomise people to, and the registry holds no trial of one. The nearest evidence is the meta-analysis of vegetarian diets — about two kilograms more loss than comparison diets over four months, through energy density and fibre — and the honest thing to say is that a plant-forward pattern may share some of that mechanism, to a degree that depends entirely on what "mostly plants" turns out to mean on a given plate. The grade reflects that: the site can describe the pattern and cannot put a number on it.
Who it tends to suit
People who want to eat less meat without a rule; families with mixed preferences; people who found vegetarian eating too rigid and want the direction without the border.
How it most often fails
By meaning nothing: "flexitarian" can describe a diet of cheese, bread, pasta and oil with occasional chicken, which is plant-forward and dense. Without the deficit built in deliberately, the label changes nothing on the scale.
What to watch
Protein on the plant-heavy days, placed deliberately with legumes, eggs and dairy; and total energy, since the dense plant foods are as dense as ever.
In the app
Nothing to verify: the balanced policy with legumes and vegetables among your preferred foods already produces a plant-forward menu with occasional meat, and the day's energy and protein are checked either way.