I spent $7 a day on food for a month—here are my top 3 money-saving tips

If you want to cut back on food costs but still eat well, there's a simple solution: Go homemade.

That's what I did for a series of Cash Diet challenges, which tested my ability to stretch my dollar at the grocery store.

While each challenge was different, all in all, I fed myself on about $50 a week, or $7 a day, and still managed to eat good, balanced meals. Not bad considering $7 in New York City will get you half a meal at any standard restaurant or one drink during happy hour.

If you're looking to trim your grocery bill — to $50 a week or just less than what you're spending now — here are my best tips for making it happen.

1. Start by figuring out how much you spend

Do you know exactly how much you spent on groceries last month? If not, look at your credit card statements or sort through your receipts. Use the data to form an estimate and then aim to cut that number.

The average four-person family loses about $1,500 a year on wasted food, so chances are, you're over-purchasing in some way. But you can't lower your bills if you don't know how much you're spending in the first place, so crunch the numbers and then set a goal like cutting your total by 25 percent.

2. Plan your meals and make a list

Before heading to the store, think about all the meals you want to prepare for the week and make a list of the ingredients you'll need for them. Then, when you're actually shopping, stick to the list. If you do, you won't spend unnecessarily on any impulse buys.

Once you have all the ingredients you need for the week, prepare as many meals in advance as you can. I've found that I'm much less inclined to order in or go out when I have my dinner prepped and waiting for me in the fridge.

3. Go cash-only

This will forever be my favorite money-saving tip. Here's how it works: If you want to keep your grocery bill at $50 a week, bring $50 in cash, and no more, to the store. Leave your credit cards at home if you think you'll be tempted to use them.

If you have the discipline to spend just the cash you've allowed yourself, going cash-only is a foolproof way to stick to any budget.

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Video by Mary Stevens