What’s the best thing you can spend money on to help lose weight?

A $1 paper notebook. Write down everything you eat, particularly how many calories it has: https://www.verywellfit.com/calorie-counting-dos-and-donts-3...

Not sure if these are the highest ROI, but I’d say discipline. Of course, you may have some underlying condition or genetics which make losing weight harder. Some basic ideas:

- being mindful of your consumption. Eat slowly, chew properly, and limit your portion.

- hydrating yourself. If you feel like snacking or eating, does drinking a full glass of water reduce or eliminate that feeling? Because it might just be you’re not hydrated.

- increase fruit and vegetable consumption. For example, a tangible investment could be taking the time to slice up a banana and an apple or two in the morning and taking them to work with you. Use that for your snack or lunch, instead of going to the vending machine or going out and ordering a burger over lunch.

- being active. Don’t sit or lay on the bed all day. Move around. Go for a walk. Do chores around the house. Take out the trash. Clean the bathroom. Get on your knees and scrub the bath tub once a week or two. You might not lose 20 pounds from this, but something like getting on your knees forces you to practice mobility. If you’re not mobile and struggle getting around, long term you’re only going to gain weight.

You could always join a gym, but I’d encourage starting with small changes in your behavior and turning them into habits. Above all else, make these habits.

You don't have to buy anything. First cut out all refined sugar then start fasting (only water, black coffee/tea) regularly once a week (36 hours) and extend it to twice a week when you're comfortable with it.

If you also want to improve your health generally, start walking.

Weigh yourself first thing in the morning and write it down. Don't be concerned about daily fluctuations, but once a week calculate your weekly average. Use that to judge progress.

In my experience, the critical key to weight loss/maintenance is consistent logging. That can be a daily tally in your head, a phone app, paper, whatever. But it must be consistent. Whether you log calories, "points", and/or nutrients is less critical, but if you're just logging calories, you'd better have some other mechanism for maintaining some nutritional balance.

If you’re data driven and can use it to make changes and adjust your behavior, a continuous glucose monitor can do wonders.

I believe that they’re prescription only in the US, and most insurance won’t cover, but it shouldn’t be too much trouble to get a doctor to write you a prescription if you’re willing to pay for it. Freestyle and Dexcom are brands that I’ve seen available.

If you consider time to be worth money, then spend time on nih.gov reading studies on weight loss. There are also a handful of decent youtubers that are nutritionists and body builders with some surprisingly decent scientific knowledge.

There are lots of things you can do for "free" making a calculation of ROI potentially tricky.

Drink lots of water and take up power walking. If you have a kid in sports then volunteer to assist with coaching.

A good pair of walking sneakers. If you're comfortable you'll keep at it. If well supporting you'll avoid pain and injury. Call that ROI or avoiding future loss.

Anything you want, which is normally too expensive to consider, but only after achieving your long term goal.

Rewarding yourself in the end can be a great method to support losing weight.

Stop eating, period.

You’re guaranteed to lose weight!

Stop eating sugar.