However, the professional athlete says she does like to indulge in her favourite foods on cheat days and she has her go-to spots when she's back in Toronto.
The tennis star, who is originally from Mississauga, says pizza is her ideal cheat day meal, but she also loves other Italian and Mexican food as well.
We asked Andreescu to name her go-to pricey restaurant in Toronto and her favourite places to get some cheap meals as well.
Here are her four top picks in the city.
Restaurant: Burrito Boyz
Address: Three locations in Toronto
Andreescu says she loves Mexican food and usually gets the chicken burrito with guac at Burrito Boyz.
"Every time I think of Mexican food and burritos that's just the first thing that comes to mind and it's not on the expensive side. Shout out to them."
The Canadian Mexican-chain is based in Ontario and has locations all over the province, including in Toronto, Hamilton, Mississauga and Niagara Falls. Despite what the name implies, you can also get quesadillas and tacos at Burrito Boyz.
Restaurant: Sotto Sotto
Address: 120 Avenue Rd, Toronto, ON
Andreescu says she also loves to dine out at the Italian restaurant and while any pasta option is a good one, she especially loves the carbonara.
North of Brooklyn Pizzeria
Restaurant: North of Brooklyn Pizzeria
Address: There are six locations in Toronto
Andreescu says she usually sticks to whole foods when she's training for a tennis tournament. However, once a week or every two weeks, the tennis star gives herself a cheat day to indulge in one of her favourite foods.
So what is an ideal cheat day meal for her?
"I love pizza so I'll probably go for a nice pepperoni pizza [...] a pizza with garlic sauce," Andreescu told Narcity.
Restaurant: Pizza Nova
Address: There are many locations in Toronto
North of Brooklyn Pizzeria isn't Andreescu's only go-to pizza place. The Canadian athlete also enjoys getting pizza at the well-know chain restaurant Pizza Nova.
"I really like the gluten free pizza at Pizza Nova."
There are locations all across Ontario so it may be easier to find and cheaper too!
This interview has been condensed and edited for clarity.