Jenna Jameson has been a vocal advocate for the ketogenic diet to help her lose 60 pounds of baby weight, and even revealed on Instagram this week what she ate — and still eats — every day following the birth of her daughter. But should fans really be following her plan for long-term weight loss?

As she described her eating habits on social media: “Every morning I eat the exact same thing. 3 eggs with cheese and an avocado. Lunch is my biggest meal, I always eat arugula salad, grilled asparagus or zucchini with some kind of meat (usually a hamburger patty or grilled chicken) I then snack when ever I feel hungry (usually on almonds or macadamia nuts… sometime cottage cheese) that’s it!

“Then I begin my fast at 6 pm. I drink lots of water until I go to sleep at around 10 pm. I drink coffee at 8 am and I end my fast at 11 am.”

Registered dietician Brigitte Zeitlin told Page Six that Jameson’s diet isn’t a healthy weight-loss plan.

“It sounds drastically under the amount of calories she needs to maintain one’s health in general,” Zeitlin, who owns BZ Nutrition, told us. “She’s also fasting for a tremendous amount of hours during the day. No, it does not sound like enough calories for an otherwise healthy human being.”

Zeitlin warned against the combination of the keto diet, which consists of eating mainly high-fat foods and few carbs, and intermittent fasting, saying it’s “not sustainable for long periods of time.” Instead, she recommends eating smaller, more frequent meals throughout the day because studies have shown that eating like that speeds up a person’s metabolism and helps maintain weight loss.

“Eventually when you do decide to eat more food [after intermittent fasting] you’ll gain weight back and likely overeat and over binge because you’ve been starving and depriving yourself for so long,” she told us. “… [It’s] not something I typically recommend unless you’ve been instructed to do so by your physician for some other medical reason.”

Before it was a celebrity craze, the keto diet was created by doctors to help treat children with epilepsy and other seizure disorders for which medication ceased to treat. Physicians found that putting children into a state of ketosis helped minimize seizures.

According to the Epilepsy Society, the keto diet has been used since the 1920s to treat the disease but “must only be followed with the support of an experienced epilepsy specialist and dietitian.”

“The ketogenic diet is conducted under strict medical supervision,” Zeitlin echoed. “It’s not a diet intended for weight loss. It was never intended for weight loss.”

Zeitlin’s “huge problem” with the diet is that it’s too low in carbohydrates, such as fruit and whole grains, which could lead to life-threatening issues because people aren’t consuming enough fiber. Low-carb diets can also lead to sluggishness and headaches.

“We get our energy and our fuel from food, so if you’re going long periods of time without eating, fueling, how are you going to be energized?” Zeitlin mused. “If you’re not eating all the foods, you’re going to be deficient in various vitamins and minerals and lacking energy.”

Zeitlin did say the foods Jameson consumes are healthy but added she’s just not eating enough of them. She also noted that it’s hard to tell what celebrities are really eating, or what type of medical supervision they’re under, from social media posts alone.

Jameson’s rep didn’t get back to us, but Jameson later posted this story on her Instagram and wrote, “Total garbage article! Nutritionists are scared of keto because it’s putting them out of business! This woman doesn’t even know my portions!!”

She added, “Your article about keto being bad, helps perpetuate America’s obesity and preventable diseases. Shame on you for trying to make me look bad for adopting a healthy lifestyle.”