Hello,
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Bulking your body is more easier then leaning your body. To lean your body firstly avoid eating junk food and remember you should maintain a strict Diet for leaning your body. Now, 1 week diet or 1 month diet doesn't lean your body it takes time depending on your body. Here are the things you should eat for leaning your body
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• Eggs
• soyabean
• Lean beef
• Chicken breast
• Salmon
• Fruits
• vegetables salad
• Curd

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Things which you should avoid

• Over eating of curd
• Dal
• Overdose of burger/pizza/Chinese food
• Chaptis not more then 2 to 3
• Eat rice accordingly because it's the best food to bulk as well as to lean

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Thing's which you should be eating daily and compulsory for Diet

• Brown bread
• peanut butter
• banana

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Now remember the more you work out the more water you should drink. 17 liters of water daily is important.  Balance the eating of veg and non veg because over eating of non veg forms more calcium which increases the risk of forming kidney stones