The former Suits star is encouraging Harry to live cleaner and he is taking her advice.
Harry, 33, has ditched carbs for quinoa and salads and is following his bride-to-be's tips as he sheds some weight.
The British Royal is determined to look in great shape for his wedding and Meghan has been motivating him to do just that.
The former hellraiser Prince has even joined a gym as he gears-up for the biggest day of his life when he marries Meghan, 36, next month in England.
A source said: "Meghan has completely changed Harry's diet. She's got him juicing and he has lost at least half a stone, which is a lot for someone as skinny as he is.
"They have bought a top-of-the-range juicer and she has him on fruit and veg smoothies. She's also weaning him off meat."
Markle is known to be a yoga fanatic who loves to eat healthy, her mother Doria Ragland, is an instructor and the pair regularly attend classes together.
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