Intermittent Fasting Beyond 50: What We Know and Don’t Know

Intermittent fasting is trending. It’s safe say some. It’s going to make you fatter say others. Whether or not intermittent fasting is right for you is the only relevant question. Intermittent Fasting (IF) has science that back results. Unfortunately, the studies aren’t on peri and post menopausal women. In this post is all I can pull together about intermittent fasting. I’ll go through a continuum of ways to introduce fasting into your life and point the pros and cons mentioned in research and studies. First, though, know that there are few clinical trials addressing fasting and few with large pools of subjects. Many of the studies existing are on rats, not people. No studies in fact, exist on midlife and older women. That, of course, even at first glance makes one wonder if you can take examples and apply them to you. There’s no denying that if you’re desperate to do anything, and looking for short cuts, it is a very attractive proposition. It is intuitive that if you don’t eat you’ll lose weight. Let’s look at the full details.

Who Should Not Try Intermittent Fasting?

Before you even consider intermittent fasting read this. If you have any of these intermittent fasting is not recommended:

• Binge eating or history of eating disorder
• Early menopause
• Blood sugar issues
• Nausea

I would add that women who haven’t established custom nutrition, exercise, sleep and stress as a foundation are also not good candidates for IF. Another key issue to pay attention to is this: women’s hormones are affected more by intermittent fasting than mens. Women, first of all have more hormones at play. Second, the negative disruption of these hormones is more likely to be a direct obstacle for desired results. Your abundant hormones are sensitive to your energy intake. These hormones in particular are of concern:

• Gonadotropin releasing hormone GnRH
• Luteinizing hormone LH and stimulating hormone FSH
• This stimulates estrogen and progesterone production
• GnRH can get thrown off by fasting

GnRH comes up not just as it affects LH and FSH but again as it’s very sensitive to leptin, insulin, and ghrelin – all of which I’ve written about as they impact your hunger and satiety. In addition, you have more kisspeptin (a protein molecule that impacts GnRH) potentially than males do.

Intermittent Fasting affects on metabolism

Your reproductive system and metabolism are deeply intertwined. If you did intermittent fasting when you were young, you’re attempts at getting pregnant may have failed. You may be wondering why you care at this point if you’re beyond reproduction. As an older adult woman, the impact is more likely greater fat storage. You’ve become the awesome house with all the closet space. If you are:

• Consuming less protein (than is required for optimal muscle protein synthesis) to begin as many women are..
• Consuming even less protein (obviously) during fasting…
• You’re ingesting fewer amino acids (building blocks of muscle)

You need to know this: Low protein diets result in less of everything known to be normal in a female cycle. This includes less libido. Estrogens are key metabolic regulators. Do something that disrupts them and you may find you store fat easier. Now, I’ve got your attention, right? Estrogens change during menopause. So you don’t care about making babies any more but you do care about those estrogens because if they go wanky you’ll store more fat more easily.

Intermittent Fasting and negative energy balance

If you’re not taking in any calories you will be in negative energy balance. Once upon a time, you may actually have thought this was the goal. Negative energy balance changes hormones. More cortisol is produced. Cortisol blocks progesterone. The dance between progesterone and estrogen that should be about equal leading and following, isn’t. That causes problems I mentioned above. It would if you were younger mean difficulty getting pregnant, missed periods, or irregular periods. Now, it’s more likely to have a bigger influence on fat. Negative energy balance comes from so many places, but I’m guessing you’re going to find yourself here:

• Too little exercise
• Too much poor quality food
• Too little exercise
• Too little high quality food
• Too much emotional stress (work, finance, relationships)
• Too little quality sleep

You see, negative energy balance is more than about calories in calories out. It’s about stress and the accumulation of too many calories, too many toxins, or a lack of the right things, all pointing toward too much stress. That is negative energy balance. What if you’re already “in” and trying intermittent fasting? My recommendations are below.

Stop intermittent fasting if:

• Digestion slows (you’re not pooping like you should be)
• Your heart rate changes
• You feel dizzy
• You have problems falling asleep or staying asleep
• You get sick or injured
• You are moody, and less intolerant to stress
• You have no interest in your partner

Just don’t start intermittent fasting if:

[This is where in my work with midlife women I often come to the conclusion on a client-by-client basis that this is NOT for them.]

• You are chronically stressed
• You don’t sleep well
• You have a history of disordered eating
• You’re new to diet and exercise for health
• You haven’t established a personal foundation that works for you

If you do decide to stick your toe in the fasting waters, I suggest  progressing through these levels in order to allow your body to adjust without stress that increases fat instead of improving fat oxidation:

• Eat stop eat (eliminate grazing: 5-6 small meals a day is a disaster for metabolism)
• Overnight and between meals
• Extended nighttime fasting (wait one or more hours after waking, as you tolerate it)
• Shortening to 8 hour eating during day
• Attempting a 24 hour (or more) fast
• A three- day reset including protein to reduce muscle wasting

Now you! Share your experience with me in the comments below. Have you tried fasting? What kind of results have you had? How did you feel during? Were your results lasting?

Sources:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4960941/

https://intensivedietarymanagement.com/women-and-fasting-part-10/

De Bond JA, Smith JT. Kisspeptin and energy balance in reproduction. Reproduction. 2014 Feb 3;147(3):R53-63.

Kumar S, Kaur G. Intermittent fasting dietary restriction regimen negatively influences reproduction in young rats: a study of hypothalamo-hypophysial-gonadal axis. PLoS One. 2013;8(1):e52416.