My suggestion is to actually do the diet with him and exercise with him. You can't expect him to make all these changes by himself when it's you that wants him to make the changes. There is ALWAYS time to exercise. Even a 20 minute workout at home will make all the difference. Find time every day to workout with him. Go on walks together. Eat healthy meals together. Do meal prep together. Having your partner do these things with you makes something like this a lot easier because you can both use each other for motivation. I'd also suggest going to a supplement shop and buy some thermogenics to help him burn the fat faster as well as carnitine to activate the liver to use fat as an energy source instead of muscles. Buying some protein is also a good idea as you can use it in cooking a lot and make food that bit healthier (try protein pancakes!) Another thing; do not have a whole cheat DAY. Have a cheat meal. A cheat day is too much. Remember as well that moderation is key. Don't change his diet from one extreme to the other. Still allow treats, but small ones to avoid him bingeing. Another suggestion is to look up healthy recipe versions of his favourite junk food. Like making ice cream out of frozen bananas, soaked dates and a scoop of chocolate protein for example. This will show him that eating healthy doesn't always have to mean you don't get to eat yummy food. Making healthy meals that taste like they're bad for you but actually aren't will be good for his motivation because it'll make him feel like he's gotten a junk food fix but he won't need to feel guilty about it. One last thing to remember is to not always just rely on the scales when checking results. Do multiple measurements as well such as waist and hip measurements and pinch test.
Pizza and M&Ms are a substitute for love and sex ,in his subconscious mind.
He can't perform, he can't lose weight, so the subconscious mind has food on the top of the list.
It's not as simple as most people may think!
The satisfaction center must be filled with something
and often it is filled with the wrong things because of another factor called "depression".
Can you just momentarily imagine yourself in an
morbidly obese body?
It might come to the point (or even at present) where choosing food over a relationship makes more sense to him, as food makes no demands and has no expectations, thus less pressure!
Do not be surprised , if in the future he may even want you go out with other men.
Among my various relationships and experiences in my younger days I once had a proposition (I've always been very fit and athletic, even now) to go out with a beautiful married woman, whose husband was obese, but I declined, despite the fact that I was physically attracted to her.
We actually had a nice discussion and it all turned out for the best, as I convinced them to go for counselling.
I suggest you do the same.
If he repeatedly refuses, it might be time to take a closer look at YOUR life.
You should ask your boyfriend to go to the doctor and get some simple blood tests done to make sure his thyroid is functioning at optimal levels. Since you said his weight began increasing a couple of years ago, it's very possible that's when his thyroid function might have began to decline.
The thyroid controls metabolism, heart rate, body temperature, as well as other body functions. If levels are off, it can mess up the entire body. Have him get tested for Free T4, Free T3 and TSH...