Research shows that around the age of 40, women begin to experience changes in their hormone production. And, since there is a correlation between intermittent fasting and hormone production, it’s only normal to wonder if there are any differences in the benefits of practicing intermittent fasting in your 40s.
I’m now over 40 and can say that I continue to feel that there are benefits of IF and that I do not experience any physical differences between fasting in my 30s and now. If anything, I feel that it has helped me stay in a routine (of sorts) and stick to healthy eating habits.
I want to first note that you should first consult a licensed medical physician before you jump into intermittent fasting. IF isn’t for everyone and therefore, it’s something to discuss with a professional.
The purpose of this post is to give you an overview of IF schedules, not to provide any professional/medical advice.
That said, when I was putting together this post and my Intermittent Fasting Guide for Women, I researched some 30+ clinical trials to see if there is anything that was specific to women in their 40s, 50s, and beyond.
What Is Intermittent Fasting?
Intermittent fasting can easily be incorporated as part of any lifestyle, even when you have kids! Fasting is where you refrain from eating for a time; so Intermittent fasting is a pattern in which periods of fasting and eating are cycled.
There are many patterns, and most are followed by personal choice, and, for women, it can be tougher with the demands of a family. Common intermittent fasting methods include 12-16 hours daily or 24 hour periods once or twice a week.
I follow the 12-16 hour fasting period since I’ve found that omitting to eat completely is tough. I usually stop eating around 8 pm and have my first real meal around noon the next day.
The only way I break my “fast” is with black or Bulletproof Coffee since its benefits are beneficial in a fasting state, and that’s usually enjoyed around 9 am, after 12-hours of fasting.
Benefits of Intermittent Fasting
The main ways intermittent fasting works for women over 40 are; weight loss, aiding cellular repair, increasing mental health and clarity, and reducing insulin resistance.
1. Weight Loss
Perhaps the more common reason people consider intermittent fasting is to reduce the amount they eat and overall caloric intake.
While I do not follow an intermittent fasting lifestyle for weight loss, eating your regular meals in a smaller time frame makes you feel full for most of the day, and therefore, most people are satiated enough that they don’t graze.
After 12 hours, your body enters what’s called a “fasted state.” In the fasted state, your body can burn fat that has been inaccessible during the fed state.
Because we don’t enter the fasted state until 12 hours after our last meal, our bodies are rarely in this fat-burning state. This is one reason why many people who start intermittent fasting will lose fat without changing what they eat, how much they eat, or how often they exercise. Fasting puts your body in a fat-burning state, rarely achieved on a normal eating schedule.
2. Promotes Cellular Repair Processes
“Sleep cures all things,” my grandmother used to say. And apparently, so does fasting.
When you sleep, your body begins to repair its cells and performs its hormonal cycles; and when your body doesn’t have to deal with digestion, it’s able to focus on the cellular repair process fully.
Cellular repair, also known as autophagy, is when cells begin to remove wastes and repair themselves. This process is required to maintain muscle mass and reduces the undesirable effects of aging. Autophagy = fountain of youth. Okay, a little exaggeration, but you get the point!
When you fast, your body can do its job in repairing itself and healing. There’s a lot of research that fasting can aid the cellular repair process with cancer and other illnesses.
3. Increase clarity and mental health
Hands down, one of my favorite benefits from intermittent fasting is the mental clarity I have in the mornings.
In this four-to-six-hour window, my mind can focus on the task and get a lot of work done. After I start eating, I’m less focused and a bit more sluggish, making my afternoons at the office less productive.
Coincidentally, two benefits of Bulletproof Coffee are mental clarity and focus. Combined with fasting, I often feel unstoppable at work.
4. Reduce Insulin Resistance
Insulin resistance is when our bodies don’t respond to insulin as they should and can’t easily take up the glucose from your blood. It often occurs due to poor diet, genetics, inactivity, high blood pressure, overweight, or obesity. Intermittent fasting is said to reduce insulin resistance.
Meaning, when your body cannot break down the sugars in your blood as it should, it begins to store them as fat. Intermittent fasting helps level out blood sugar levels.
Intermittent Fasting for Weight Loss over 40
Intermittent fasting alone will not help you lose weight if you’re over 40. It is not a magic pill. Results are person-specific and depend on lifestyle, activity levels, dietary intake, and more.
Can you lose weight by incorporating intermittent fasting into your already healthy lifestyle? Absolutely and it depends on everything else you do. I know this is a very frustrating answer, but that’s the truth. Read about how I started running at 40 here.
Some people report between 2 and 8 pounds per month by only adding IF to a healthy diet. If you have kids, eating a consistently healthy diet can be frustrating since kid-friendly foods are not usually healthy.
Types of Intermittent Fasting for Women
There are several ways to approach intermittent fasting and ultimately, the best fasting schedule is one that works with your lifestyle and specific needs.
Most importantly, a schedule you can incorporate into your daily life.
Daily 12 to 16 hours fasts
For a 12 hour fast, you would eat between 8 a.m – 8 p.m. A 16-hour fast would have an eating window between 12 p.m and 8 p.m. More about 16:8 intermittent fasting here.
24 Hour fasts
No food intake for a full 24 hour period done once or twice a week.
Consists of 5 days with regular eating and 2 fast days in which calories are reduced to 500-600.
Alternate Day Fasting
Fasting every other day. Some versions allow 500 calories on fast days.
You can, of course, alternate days and schedules to keep it fresh and interesting. It’s your personal choice. Watch this video to learn more about what foods women over 40 should eat when Intermittent Fasting.
Fasting in your 40s Differences
I personally feel that women experience a lot of physical changes, mostly due to hormones, in their 40s; and anything that can aid with the stabilization of hormonal production is a plus in my book.
After having 3 kids, I personally feel it’s more difficult to keep my weight stable now that I am in my 40s; especially so now that I have a few thyroid issues.
This makes it more important than ever to begin to look at your health as a lifestyle rather than a temporary fix of a problem. You can always work with a registered dietitian that specializes in your particular area of need (thyroid, type 2 diabetes, high blood pressure, etc).
Several studies noted that when women followed an active lifestyle and included a variety of foods into their daily nutrition program, they felt physically and emotionally healthier.
Intermittent Fasting in your 40s Getting Started
Getting started is simple. In fact, chances are you’ve already done many intermittent fasting days before. Many of us instinctively eat this way, skipping morning or evening meals -not always on purpose but because we’re not hungry or full from eating a larger meal in the afternoon.
The easiest way to get started is to choose one of the intermittent fasting methods above and give it a go. However, you don’t need to necessarily follow a structured plan.
If you want to dive deeper, I’ve created a book with everything you need to know about intermittent fasting & a 1-week meal plan so you know exactly what to eat during your eating windows. Check out my Intermittent Fasting Guide here.
Intermittent Fasting Research
If you’d like to expand your reading, check out some of the research below.
- Carter S, Clifton PM, Keogh JB. Effect of Intermittent Compared With Continuous Energy Restricted Diet on Glycemic Control in Patients With Type 2 Diabetes: A Randomized Noninferiority Trial. JAMA Netw Open. 2018;1(3):e180756. Published 2018 Jul 6. oi:10.1001/jamanetworkopen.2018.0756
- Catenacci VA, Pan Z, Ostendorf D, et al. A randomized pilot study comparing zero-calorie alternate-day fasting to daily caloric restriction in adults with obesity. Obesity (Silver Spring). 2016;24(9):1874-1883. doi:10.1002/oby.21581
- Harvie MN, Pegington M, Mattson MP, et al. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int J Obes (Lond). 2011;35(5):714-727. doi:10.1038/ijo.2010.171
- Harvie M, Wright C, Pegington M, et al. The effect of intermittent energy and carbohydrate restriction v. daily energy restriction on weight loss and metabolic disease risk markers in overweight women. Br J Nutr. 2013;110(8):1534-1547. doi:10.1017/S0007114513000792
- Hutchison AT, Liu B, Wood RE, et al. Effects of Intermittent Versus Continuous Energy Intakes on Insulin Sensitivity and Metabolic Risk in Women with Overweight. Obesity (Silver Spring). 2019;27(1):50-58. doi:10.1002/oby.22345