Brief Answer:
not safe

Detailed Answer:
Hello and thank you for your question.
The lemonade diet is part of a cleanse program that is not really necessary for good health. The body does not really need a cleanse if you put healthy food into it. If you eat a lot of junk food then the best thing to do is to change to a healthier eating plan. In the lemonade diet you drink a mixture of lemon juice, maple syrup and cayenne pepper for a few days. This gives you no protein or fat to help your body process its energy needs and could leave you feeling tired and drained.
Most young healthy people could do it without too much danger but people over fifty it could cause problems in the stomach, intestines or kidneys.
I suggest that you just choose to eat more fresh fruits and vegetables and avoid processed foods. This will improve your health without a risky cleanse.
Best wishes,
Dr. Robinson

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