Transcript for The Secret to Beyonce's Met Gala Bod
Also on the heat index, won says met gala look. It caused quite a buzz. So many wondering how she did this. Paula Faris tells us what's behind the vegan plan she used to get fit. Reporter: Queen bey, the belle of Monday night's bet ball. Showing off her every curve. People using the hashtag flawless. This is her at last year's gala. Con paired though this week. How did she make the transformation? By going vegan. Eliminating all animal products from her diet. Even butter. The grammy winner and Hur hubby, jay Z, first taking a2-day vegan challenge back in 2013. Then they kept going. Following the advice of Marco borges, bee Yoon says trainer. It couples habit formation with plant-based nutrition. Yor adopting new habits. Reporter: His major rules. Choose plants over processed. Eat three meals a day, focusing on carbs over protein and fat. Exercise for a half hour every day. Last but not least, drink plenty of water. But being veeg season not a piece of cake. ? You can miss out op nutrients. B vitamins. Omega 3 fatty acids. There are so many things you could be lacking. Reporter: 27-year-old Hannah has been vegan for over a year. She says she loves the way it makes her feel. But says there is a high price to pay. It can get pricey. But the investment you make there is where you wnt to make it instead of at the doctor's office. Reporter: What happens on day 23 when you stop the diet? Anytime you discontinue a very restrictive dietary regimen, and go back to your habits, you're going to gain the weight back if you don't have an action plan. Reporter: Still, borges says going vegan can change your life. With diet and behavior modification, we can live much, much healthier lives than we're living today. Reporter: For "Good morning America," Paula Faris, ABC news,
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