The following is a summary on the carbohydrate-health-hormone connection compiled by Dr. Tamsin Lewis (aka my UK sister), and it’s based on science presented in a Chris Masterjohn podcast—too good not to share with you guys. Tamsin is a former professional triathlete and medical doctor with a similar past as mine—we both struggled with eating disorders, hormone imbalances, and overtraining, among other female health issues, and we’ve both made huge efforts to recover, regain great health and climb the ladder to self-optimization. She and I now do our best to promote wellness, not trendy diets and fads, which entails not only high-level performance on the outside but also high-level performance on the inside, including optimal hormone functioning—the stuff that really matters. Tamsin is a reoccurring guest on Endurance Planet, if you’d like to hear more from her.
For the Masterjohn podcast that inspired this post, click here.
Also, please leave your questions and comments below the post!
Sex Hormones and Diet
Fertility
Fertility is an energy expensive process. The body needs to perceive that it is in a position to be able to “afford” to expend this energy. Even if the aim is not to have a baby right now, optimal sex hormone status coffers optimal virulence for male and females.
Fertility is closely related to critical body fat; by Rose Fisch (1970):
- 17% for menstruation
- 22% for healthy fertility
Leptin
Leptin is a hormones produced by fat cells (from body fat) and it’s how the body communicates with our brain on how much body fat is present for fertility, etc. More specifically, leptin is produced by fat cells proportionate to their number/mass and feeds back information to the hypothalamus (the governor) in the brain. This communication controls the Hypothalmic Pituitary Gonadal (HPG) Axis. In other words, the brain controls the ovaries/testes via the hypothalamus control center.
So adequate leptin levels are needed to signal to the brain to produce sufficient signaling molecules (FSH > ovaries/testes; TSH > thyroid) so that those organs then produce enough hormones.
There is also the Hypothalmic Pituitary Thyroid (HPT) Axis—the brain control of thyroid hormones. And the Hypothalmic Pituitary Adrenal (HPA) Axis—brain control over adrenals and stress hormones, which is one that often comes up with athletes and overtraining. It’s all related…
Thyroid
Thyroid stimulating hormone (TSH) is what increases thyroid hormone output. This process allows cholesterol to be taken up from the blood and used as a building block to make sex hormones. (When hypothyroidism occurs, TSH will increase even more as a way to tell the body that more thyroid hormone is needed; not a good thing if active thyroid hormone is still suffering, i.e. T3, the more metabolically active thyroid hormone, and usually there are underlying cause for this including diet choices.)
So adequate thyroid hormones are necessary to make adequate sex hormones. The thyroid governing the provision of the building blocks for sex hormone production and FSH allowing that to be converted into sex hormones.
And back to leptin: Leptin was the missing link until 1970s; before this we didn’t know how body fat regulated fertility. Leptin ++ >> HPT + >> HPG axis.
Insulin
Insulin regulates energy expenditure. It is a signal of energy status and promotes antioxidant defense system. Insulin acts on the thyroid gland to produce thyroid hormone and assists in conversion of T4 to T3 (again, T3 being the more metabolically active thyroid hormone).
Whilst leptin is a signal for long-term energy status, insulin is a marker of short-term energy status. Insulin is strongly stimulated by carbohydrate intake and because we can store far less carbs than fat in our body, if carb intake is, insulin signaling will be low.
The body is more likely to engage in fertility when both leptin and insulin signals are robust, and when we do not have immediate strains on our energy as reflected in elevated stress hormones, e.g. cortisol and inflammation (hsCRP and Homocysteine are both markers you can test in blood to assess inflammation).
This is true for both men and women (not just women!).
Summary So Far
On leptin: Leptin is necessary for both male and female fertility, but it is not enough just to have enough leptin (e.g. fat mass)—you also have to be sensitive to it. If you are obese or inflamed you will lose sensitivity. How do you ensure you’ll be sensitive and not inflamed? Maintain just the right amount of body fat, which is 18-25%. (Some endurance athletes may be cringing that these numbers are “high,” but it’s the reality of it.)
On insulin: You can be maximally sensitive to insulin on a low-carb diet, but if there is no insulin (which happens when carb intake it too low) then the cholesterol uptake into cells that’s necessary for hormone production is going to be inadequate. So there’s no point in being very sensitive to insulin if you are not producing much insulin! Same goes for obese or diabetic patients where there is insulin resistance—the signal for hormone production is not getting through, i.e. the key doesn’t fit in the lock anymore.
Case Study Example
Subject: A physician diabetic who tried a low-carb (LCHF) diet & the resulting problems:
- TSH increased (not good)
- Sex hormones low (also not good)
- Good sensitivity to leptin and a good amount, but insulin signal not getting through
- Evolutionary context in terms of what our brain is processing: “I’ve had plenty abundant energy (insulin/carbs) for years, and now that signal has been removed—so the body sees this as really not being a good time to bring a baby into the world. Plus if chronically restricting carbs to have low insulin then it is never going to be seen as a good time by the body. This could results in chronic suppression of the thyroid and sex hormones.”
The stress response and the inflammatory response are saying to your body, “we need to redirect energy away from long-term energy-intensive health-promoting pro-fertility responses, and into these other responses that are needed right now at this moment.”
Can LCHF Ever Work?
So, then, who are the folks who do well on a LCHF diet in terms of maintaining sex hormone levels? Here are the criteria:
The are NOT:
- NOT sleep deprived
- NOT inflamed – related to diet, over-exercising, under-exercising
- NOT overtrained
- NOT overworked
- NOT given birth to 2+ children
They ARE:
- Psychologically and emotional resilient
- Have a good social support network
- Solid relationships with family and friends
- Stress response is appropriate to the stimulus/context
- Adequate in body fat levels but not too much
- Physically active but not OVERactive (sorry, endurance athletes)
- Making enough leptin and are sensitive to it
- Making enough thyroid
- Insulin levels sufficient
- Their HPG Axis is active
- Inflammation/stress response minimal
…And there you have it, the folks who can likely do well on a LCHF/ketogenic diet and maintain good hormonal status. Pretty strict criteria, eh?
The problem is when we take that “ideal” person above and generalize it to other people who don’t have the criteria optimized. Maybe we tell them to optimize their lives without really giving a good strategy to do so , or let’s face it, maybe it is just not possible to truly meet those criteria whether by choice or not. Heck, it can be a complete life overhaul.
Conclusions
Be clear about your reasons for adopting LCHF or a ketogenic diet. With diabetes we can see the rationale, but we often still ignore the fact that keeping insulin super low can present problems with antioxidant defense, thyroid, and sex hormone regulation as discussed above.
Also ask yourself: are you just jumping on a band wagon because it is ‘in vogue’ to go LCHF or try ketosis; because you heard it worked for someone else?
Be skeptical. Don’t buy into the “magic pill” solution.
Meanwhile, track your biomarkers and health:
- Sex Hormones (Testosterone, SHBG, FAI)
- Thyroid Hormones (TSH, free T4, freeT3)
- Lipid Panel and cholesterol subfractions if LDL is raised.
- Fasting blood glucose (BG)
- Postprandial BG – as often as you want and try not to get OCD about it
- Insulin
- Track your body composition.
- Track how you feel. Not just after one week but after one month, two months, three months.
Tawnee Here…
Most often I see LCHF go seemingly “ok” until about the three-month mark and that’s when things start to “blow up” if you will, especially if the person is training (strength or endurance) or simply exercising heavily (like most of my clients). It’s not just me seeing this. I know Tamsin and other colleagues are seeing the same. Females are usually are more sensitive and become worse off than males, but in 2016 I saw more “dysfunctioning” males than I’ve ever seen—LCHF experiments gone bad, if you will.
The list of criteria outlined above to “qualify” for LCHF are truly very hard to achieve, and I know very few people in the modern world who fit the bill. You really have to get honest with yourself in making the assessment, and then ask…. is it really worth it?! More often than not, most of us will not meet all the criteria and maybe that’s ok. I don’t say this to be pessimistic but rather just speak the truth. We can still strive to meet the criteria regardless of carbs, and we can still become optimized with carbs in our diets 😉
I’m sure some are still wondering: What’s the answer with nutrition if too many carbs (and junk) are bad and if too few carbs are bad? At the end of the day, I love what Peter Attia says on diet/nutrition, and I am paraphrasing here: I don’t care what you eat—vegan, paleo, South Beach, Ornish, whatever—as long as you’re managing blood glucose (BG). The name of the game is glucose disposal, so maintaining low BG averages and low BG variability is the ticket to health success. We’re all different—genetics, epigenetics, lifestyle, and so many other factors play a role into each of our ideal diets—so do the work from a health-perspective to figure out your ideal diet. A good place to start is simply monitoring your BG, which will also give some foresight on insulin sensitivity and regulation.
Plus as this post points out, not only BG monitoring matters, but monitoring sex hormones and other markers of health matter too. You don’t need to be baby-planning for this to be important, there’s a lot more on the line to building a well-functioning body.
Lastly, this article is not meant to say that everyone can go back to pizza, donut and bread diet. Not that simple. There are plenty of people out there who still need to decrease carbs and focus on better carb quality (thus going “lower carb”) to get into the sweet spot for optimal health. And on the flip side, there are those who need to desperately add back more quality carbs after going too low carb for too long—and reboot the system. Then’s there everything in between. It’s the individual’s needs that matters most not how many grams of carbs you can get yourself to stick to each day.
And don’t forget—your brain is always listening and sending out information to the body. That can’t be emphasized enough.