3 Differences Between Men & Women On A Keto Diet, According To An R.D.

Integrative functional medicine practitioner Ali Miller R.D., L.D., CDE, has a passion for the food-as-medicine protocol, as she uses nutrients and food as the foundation of treatment in her practice. 

It only makes sense that she’s a supporter of going keto, as she personally follows a keto diet and believes it’s actually a natural way of eating. “Breastfed babies are keto; even in utero, babies use ketones for survival,” she notes on this episode of the mindbodygreen podcast. 

She believes keto is an important eating plan for combatting anxiety, taming inflammation, and balancing blood sugar—all important topics we discuss during this episode.

However, it’s important to recognize that while keto can have significant benefits for our health, not all keto eating plans are created equal. On a personal note, I was raised by women and currently live in a predominantly female household with my wife and two daughters; I’ve since recognized how there could be differences between men and women in terms of nutrition and hormone balance, especially when it comes to following a keto diet. 

Miller agrees: “How men and women are different is that men generally hold more muscle mass and women generally hold more body fat,” she tells me. However, it’s not as simple as body fat—she explains just how (and why) men and women differ as they follow a keto diet.  

One of the main differences between men and women is their sensitivity to leptin (a satiety hormone). Miller explains that it's these leptin imbalances that probably segregate men and women most on a keto diet.

What she means is that a keto diet focuses on carb restriction in order to produce ketones, which in turn reduces the leptin hormone. Women have leptin receptors on the thyroid in their ovaries, so women have a lot more leptin sensitivity than men. This can be an issue, because leptin levels that are too low can influence anxiety, insomnia, and hunger over time. 

The good thing is, menstruating women can use their menstrual cycle as a sign that their bodies are A-okay while following keto. 

“Women's menstrual cycles are really a regulating sign that the body is safe or balanced,” Miller says. 

So, if a woman’s menstrual cycle is more irregular than usual, it could be a sign that her body is not responding well to keto or that her leptin levels are too low. According to Miller, that’s when it could be beneficial to start carb cycling. 

“I see a big variance with women needing carb cycling often, especially if they're at a low body fat, they exercise, and they don't sleep enough,” she adds. 

In almost every other case, determination is an admirable, redeeming quality—so many women Miller sees in her practice have this incredible drive to accomplish their goals, and do so meticulously. 

However, when it comes to keto, Miller says that this quality can sometimes do more harm than good. With all of the leptin depletion and hormone dysfunction that can come with unsupervised keto, women’s bodies might not feel safe enough to carry a child, which can lead to the loss of her menstrual cycle. 

Miller frequently sees this type of client. “Women that are type A go-getters, that want to do all of the things, and they don't actually have that much weight to lose—it might be three-to-five pounds, or just a mere composition change," she tells me. "If they layer fasting, as well as tight carb restriction, often their leptin levels decline, and the body says ‘I’m not safe.’”

So this perfectionism that can come with keto (and intermittent fasting, for that matter) can have a dark side. It’s important for women to know when too much is simply too much so that their hormones remain balanced—a piece of advice that we can apply to men, too, but especially women following a keto eating plan.