First of all, there is a reason that this tabloid is normally referred to as the "Daily Fail." Second of all, it isn't new. Third, it's more proof that most of don't know the basics of how our body systems work and work together.
The reasons why this is nonsense has already been adequately and succintly covered by Dr. Gabe Mirkin over at Quackwatch. But let me highlight this paragraph right here:
"Dietary modification cannot change the acidity of any part of your body except your urine. Your bloodstream and organs control acidity in a very narrow range. Anything that changed acidity in your body would make you very sick and could even kill you. Promoters of these products claim that cancer cells cannot live in an alkaline environment and that is true, but neither can any of the other cells in your body."
In other words, your body is doing just fine on it's own as far as controlling pH levels is concerned; if it wasn't, you would be dead before you could whip up your batch of beetroot and walnut dip.
Now, is there still an advantage to getting rid of your high caloric soft drinks/coffee drinks/alcohol and other added sugars? Of course, because you are reducing your calories, which will help with your weight, and you are reducing your carbohydrate intake which will help those of us with insulin-resistant problems like diabetes and pre-diabetes (and the high blood pressure and cardio-vascular diseases that go along with that). You also get to fill up on the nutrient dense, but still low calorie, items like vegetables and some fruits. But, you will also likely be shorted on protein (as even beans are limited!), and I have written before about the pitfalls of raw diets. And do people really think these celebrities prepare the food themselves? Really?
Take home message--There are still good reasons to fill up your diet with fruit and vegetables and avoid processed/low nutrition foods, but changing your blood pH isn't one of them.