Brief answer....whey protein is totally safe.
Detailed answer.....
Hello,
Thanks for the query.
 Whey protein comes from cow's milk, is a rich source of the body's essential amino acids, is efficiently digested and absorbed and is the most nutritious protein available.
As you already know, protein is an important nutrient needed on a daily basis. It's made up of essential and non-essential amino acids, which are the building blocks for healthy bodies. Protein has a number of different roles in the body such as repairing cells, building and repairing muscles and the production of energy. 

Compared to other proteins, on a gram-to-gram basis whey protein delivers more essential amino acids to the body but without the fat or cholesterol.

 Whey protein is safe for most adults,however high doses can cause some side effects such as increased bowel movements, nausea, thirst, bloating, cramps, reduced appetite and tiredness in some people.
You can safely consume it in safe and normal doses.

I hope it helps,however you may revert to me for any further query.
Best of luck
Thanks

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