Amenorrhea and bone health

I know a lot of chicks who do not have their period. Most of whom aren’t looking to get pregnant yet, so they don’t really see it as much of an issue. Some even see it as a blessing.  I get that. Periods are a little inconvenient. They are messy. They hurt. BUT they play an important role in our health. As women, getting a regular, monthly period signals that our menstrual cycle is healthy, our hormones are working as they should be and we are capable of reproducing, if we so wish. Our period, in a way, is the canary in the coal mine. 

Image by Manita Brug via Pinterest 

I often refer to my period problems as “hypothalamic amenorrhea” (HA), which is basically a diagnosis of exclusion. I don’t have PCOS. I don’t have a tumour on my pituitary gland. I don’t have a physical problem with my ovaries. I do have a problem with the message getting from my brain to my ovaries to produce sex hormones. Another term for this whole biz is the “Female Athlete Triad” – FAT (or lack there of it, in this case). FAT refers to a constellation of 3 clinical entities:

1. Menstrual dysfunction
2. Low energy availability (with or without an eating disorder). When I say “energy availability”, I am referring to the amount of energy left over for all of your bodily functions after taking exercise into account. If you are eating 2000 calories per day and "burning" 2000 calories per day, you're in trouble!
3. Decreased bone mineral density

Today I’m going to focus on the third point as this applies to all females, regardless of whether they want to make babies or not. I am pretty sure none of us wants a fractured hip before they hit their 40’s (which, scarily, is a more common occurrence than one would think). It's a bit of a long post, but incredibly important (and filled with loads of fun science. You know you love it). If you're time-short, just read the bold points and then take some action. 

Image by Alec Paloumpis via Pinterest

In February last year, I had a DEXA scan, which revealed my bone mineral density (BMD) was less than optimal. My response: Oh. Fuck. Considering my peak bone mass had already been obtained and I would start to lose BMD in less than 2 years, this was not the easiest thing for me to process. So I didn’t. I focused more on the infertility side of things instead, because that was what I was more concerned about at the time.

Let’s back up a bit. Why does amenorrhea cause bone loss? It’s a little bit sciency, but I think you can handle it. Maybe a picture will help? Here you go. Just look at the right hand side. The left hand side is a talk for another day.

 

Image via www.sfu.ca

In a normal, fully-functioning, female, part of the brain (the hypothalamus) will release something called Gonadotropin Releasing Hormone (GnRH). You can think of this in 2 parts to make more sense: “gonad” = ovaries, “tropin” = increase/stimulate. So GnRH signals to the pituitary gland (also in the brain) to “release” gonadotropins. These are Follicle Stimulating Hormone (FSH) and Luteinising Hormone (LH). FSH and LH then stimulate the ovaries to produce and secrete sex hormones (namely estrogen and progesterone) in a cyclic manner.

In someone with HA/FAT, the GnRH secretion is thrown all out of whack due to stress, too low body fat and/or not enough food to play with. As a result, down yonder in the ovaries, no message comes through to produce sex hormones, so they go on vacation. Ergo no estrogen. No progesterone. And, often, no testosterone. Boo. While all of this is pretty crappy, the bone complications come about due to the lack of estrogen, termed “hypoestrogenism”. Big words today, people. Are you still with me?

Why is estrogen important in bone health? I am going to simplify this with a list, given that your brain might be overloaded a bit already:

1. Estrogen stimulates bone formation
2. Estrogen suppresses bone resorption (whereby bone is broken down and the minerals are released, resulting in a transfer of calcium from bone to blood)
3. Estrogen inhibits osteoclast activity (osteoclasts break down bone, as opposed to osteoblasts, which build bone)
4. Estrogen is responsible for the expression of vitamin D receptors i.e. it plays a role in vitamin D actually doing its job in helping to build bone

Now, the process of bone breakdown and formation is incredibly complex, but this hopefully gets my point across – estrogen is important for bone health. No estrogen, no bones. Well, not really. You probably won’t turn to mush.

45-50% of our peak bone mass is formed during puberty. By the time we are 18, we will have reached ~90% (unless you have HA/FAT when you’re a teenager – then the picture ain’t so pretty). From the age of 30, if all is working well, we will lose ~1% of our BMD per year. HOWEVER…

If you have HA/FAT, the rate of bone loss is similar to that seen in menopausal women: ~5% per year. That is 5 times greater bone loss than we should be losing! 

If that doesn’t scare you, then I do not know what will. Maybe go and hang out at a geriatrics ward and take a look at what recovery from a hip fracture looks like.

One study found this: “The lumbar (lower back) BMD of [runners with amenorrhea] was found to be lower than the BMD of an average 50 year old woman”

Shitballs. Here are some more scary findings, just in case that is not enough to get you out of your whole “it’s convenient to not have a period” funk:

The bone loss that occurs in women with amenorrhea is most likely irreversible. I repeat – irreversible. You can take all of the calcium supplements you want, but you probably won’t get it all back. You might get some, if you are very serious about making some changes.

Another study on 27 women with an average age of 21.8 years with functional hypothalamic amenorrhea had reduced bone mass throughout the whole skeleton.

The length of time that someone has amenorrhea is negatively correlated with BMD. Read: the longer you have no period, the shittier your bones will be. Read: go and do something about it NOW!

Exercise is not sufficient protection. When I had my DEXA, the lady said “you should do some more weight bearing exercise”. No shit Sherlock. I’m a personal trainer, group fitness instructor and I have been doing weight bearing exercise all of my life. But thanks for your input.

Hormonal therapy (e.g. the oral contraceptive pill) is not sufficient if satisfactory nutritional status is not achieved. There is no magic bullet, ladies. You have to do the ground work and fix the underlying cause.

So what’s a gal to do?

Well, firstly, don’t ignore it. It will only get worse with time. If you have had amenorrhea for more than 6mths, get a DEXA scan to see how your BMD is looking. Then get another one every year after.

Secondly. Fix it. This is more complicated than I like to admit. I am in the process of writing a book about this now, which will take some time, but I am committed to the cause.  Read my other posts on hypothalamic amenorrhea as a start - HERE, HERE, HERE and HERE. Yep, there are a few of them. And there will be more, but I am moving from focusing about me to focusing about YOU!

Start with eating more (and eating well), exercising less, but still do some exercise. Yoga is great for bringing everything back into balance. Weight training, in small to moderate amounts, is good for helping with bone and muscle strength.  Don’t run. Don’t do more than 30mins of cardio at any given time. Just don’t. Research has shown that just 20 minutes of quiet standing on a vibration platform can decrease and prevent bone loss. And it feels pretty good – it shakes your body awake!

That’ll do for now. Thanks for hanging in there, friends. Please share this with anyone who you think might benefit from it.  Our skeleton is pretty important. Let’s make sure we don’t lose it before our time. PS have you checked out the Thyroid Sessions yet? They are pretty awesome, and free for a limited time. Fun fact: thyroid problems can cause amenorrhea. Click HERE to watch now. 

Studies used in writing this post:

• Constantini, NW. & Warren, MP. (1994) Special problems of the female athlete, Bailliere's Clinical Rheumatology, Vol 8, Iss 1, pp199-219
• Ackerman, KE. et al (2012) The Female Athlete Triad, Sports health, Vol 4, Iss 4, pp 302 - 311
• Deimel, JF. & Dunlap, BJ. (2012) The Female Athlete Triad, Clinics in Sports Medicine,  Vol 31, Iss 2, pp 247 - 254
• Nissenbaum, JT. (2013) Long term consequences of the female athlete triad, Maturitas, Vol 75, pp 107-112
• Pludowski, P. et al (2012) Skeletal status and body composition in young women with functional hypothalamic amenorrhea, Gynecological Endocrinology, Vol 28, Iss 4, pp 299-304