Lunch is a protein-packed salad, her afternoon snacks include apples with almond butter and a green juice, and dinner is always pasta with zucchini and cheese - all washed down with a glass of wine.
The star's diet becomes even more relaxed when she't not filming, when she loves to gorge on french fries, toast, and Canadian funnel cakes smothered in caramel, chocolate and marshmallows.
"French fries and vino are my vices," she added of her relaxed approach to eating.
Meghan, who was seen picking up groceries recently at Whole Foods in Kensington - a stone's throw from her boyfriend's Kensington Palace abode - also proved she's got culinary skills after sharing her kitchen secrets.
Meghan loves to slow cook her zucchini for up to five hours, at which point, she says, it turns into a "filthy, sexy mush", which she pours over pasta.
"The sauce gets so creamy you'd swear there's tons of butter and oil in it, but it's just zucchini, water and a little bouillon," she said of her cooking hack.
Meghan, who swears by green juices to boost her health, also loves to spritz her steak with lemon, which she says brings out the flavour.
While her boyfriend was teetering on the edge of Guyana's Kaieteur Falls, which are 820ft high, Miss Markle, 35, was playing dress up with her dog and buying herself flowers over the weekend.
And just in case Harry, 32, had forgotten her, the American actress chose a Union Jack themed coat for her pet Guy.
It came only hours after she was pictured supermarket shopping in Toronto wearing a baseball cap and green parka jacket and pushing a laden trolley through the car park.
Miss Markle, who often writes about her love of the simple things in life, was seen stocking up on basics such as kitchen roll and water during the outing.
