Pros and cons of the alkaline diet

Whether you find her figure enviable or unappealing, when Victoria Beckham talks diet, a lot of people listen.

Some say she single handedly made the book Skinny Bitch a best seller, after she was photographed carrying a copy, and her casual mentions of little known products like Pu-erh tea have resulted in skyrocketing popularity.

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Now, her recent tweet, about a cookbook that advocates an alkaline diet, has generated quite a buzz about this way of eating, which has reportedly attracted other celebrity fans including Jennifer Aniston, Gwyneth Paltrow and Kirsten Dunst.

In a nutshell, the theory behind the alkaline diet is to eat in a way that optimizes pH balance, by avoiding meat, dairy, sweets, caffeine, alcohol, artificial and processed foods, and consuming more fresh fruits and veggies, nuts, and seeds. But there's a little more to it than that. Here's my take on the pros and cons:

Con: The research is limited
Many health professionals dismiss an alkaline diet as completely unnecessary, because our bodies are inherently designed to maintain pH balance. But, there isn't a whole lot of research on the subject. A 2012 report, published in the Journal of Environmental and Public Health, reviewed the published studies and basically drew mixed conclusions. The bottom line: the key benefits of this approach seem to stem from guidelines you've already heard a million times—eat more fruits, veggies, and plants, cut back or cut out sugar and processed foods, and slash your sodium intake.

Pro: One rule may help you preserve muscle
Fruits and veggies are the foundation of an alkaline diet, and all that produce may help you hang onto calorie-burning muscle mass. We lose muscle as we age, but one recent study found that older adults who consumed more foods that are metabolized into alkaline residues (mainly fruits and vegetables), and fewer foods that are metabolized into acidic residues (mainly proteins and refined grains), hung onto more muscle mass. The effect was nearly enough to offset the 4.4 pounds of lean tissue that older adults typically lose per decade (imagine four pounds of lean sirloin), which could have a significant impact on strength, injury risk, and metabolism.

Con: It can get confusing
The lists of foods that are alkaline versus acidic are not intuitive. For example, lemons and apple cider vinegar, which are acidic in nature, are listed as alkaline, due to how they are metabolized in the body. Also, the acid-forming list includes some of my favorite healthy foods, such as cranberries, pomegranate, chickpeas, walnuts, and tea. To be fair, while these foods aren't entirely off limits, I question the need to ration them. Also, in searching online, I found several versions of the alkaline/acidic charts, some with the same exact food, such as quinoa, listed in both categories. Others break foods down into sub categories, like extremely, moderately, or slightly alkaline or acidic. Finally, some advocates recommend a 60/40 alkaline/acid ratio, others 80/20, and portion guidelines vary. Because the alkaline diet is more a theory than a program, there is no one accepted structure. Here are some examples of foods you can eat on the alkaline diet: edamame, artichokes, broccoli, almonds, coconut oil, and kale.

Pro: One rule may help you may look younger
One of major tenets of an alkaline diet is to avoid refined sugar, and following just this rule alone may help your skin remain more youthful. In one study, Dutch researchers asked volunteers to look at photographs and guess the ages of over 600 people. They found that the pictures of those with higher blood sugar levels were perceived to be older. This may be because of the connection between sugar and the formation of a substance called advanced glycation end products or AGEs, which have been shown to reduce skin elasticity (think sagging). Not a bad reason to ditch a sugary breakfast muffin and whip up a smoothie instead.

Con: You may not lose weight
In my years counseling clients, I've seen many people go vegan, or switch to a super clean diet, and still not lose weight. This is typically because they overdo it on the good stuff, and unfortunately, any time you consume more than your body needs to support your ideal weight—even from superfoods—the surplus winds up feeding your fats cells. Weight loss requires not just avoiding bad foods and eating good ones, but also eating the right portions for your body's needs.

Pro: You may lose weight!
I know I just said you may not, but IF you don't overdo it on portions, this style of eating may offer a weight loss advantage. Eating a vegan or mostly vegan diet is associated with being leaner. One Oxford University study in nearly 38,000 adults found that meat-eaters had the highest BMIs for their ages and vegans the lowest, with vegetarians and semi-vegetarians in between. Also, some fascinating research has found that even at the same calorie level, people who consume more plant-based foods and have higher antioxidant intakes had lower BMIs, smaller waistlines, and lower body fat percentages than those with lower intakes.

I'm always intrigued by nutrition theories that while not yet "proven," may pan out with more research, so this is one I'm going to watch, particularly because its basic principles mirror what I've been recommending for years. An alkaline diet philosophy may become as mainstream as gluten free, or fizzle out entirely. Regardless, I hope that its emphasis on eating more fresh, plant-based foods, and getting rid of the junk, is here to stay.

This article originally appeared on Health.com.