A new report suggests that Katie Holmes' recent weight loss is down to a Scientology-based detoxifying health regime.

The actress - who has been looking tired and drawn in recent weeks - is said to be trying out a purification program known as Clear Body, Clear Mind.

The program consists of exercise, saunas and vitamins and minerals to help cleanse the body.

It's claimed that Katie embarked on the gruelling dotox during her run in Broadway play All My Sons and has lost a dramatic 22lbs as a result.

"When Katie embarked on a new diet, Tom was insistent that it stick to the codes of Scientology," an insider tells Woman's Day magazine.

"The purification program is all about ridding the body of harmful toxins and calls for cutting out refined sugar, junk foods and carcinogens that create toxicity.

"It's very gruelling - long periods of fasting on nothing more than water and juice, and heavy doses of niacin, colonics and long heated saunas to purify the body."

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