If you’ve found yourself gaining weight during perimenopause or post menopause, you’re far from alone.

Research suggests that around 50–70% of women experience some degree of weight gain during this life stage (Scope & study).  

Studies show that women typically gain around 1 to 1.5 pounds (about 0.5 to 0.7 kg) per year during the menopausal transition (study & study).

While that may sound modest, it can add up over time — and for some women, the weight gain can be more pronounced.

And it’s not just about the number on the scale. Body composition often shifts too, with fat more likely to be stored around the waist which can feel confusing and frustrating, especially if eating or activity habits haven’t shifted much.

These changes are common, and they’re influenced by hormonal shifts, changes in metabolism, and how our bodies naturally adapt with age – see my blog on why do we gain weight and change shape during menopause.

If you’re noticing that weight gain — particularly around your middle — is affecting your health, energy, or confidence, it’s understandable to want to explore options.

You don’t need to aim for an “ideal” weight or strive to look like you did in your 30s, even modest weight loss — around 5–7% of current body weight — can support better metabolic health and reduce the risk of conditions like type 2 diabetes and heart disease (study & study).

It’s no surprise, then, that many women in midlife are looking for ways to manage these changes — and one approach that’s attracted a lot of attention is intermittent fasting (IF).

IF has become an increasingly popular approach to managing weight and improving metabolic health — and many women in midlife are curious about whether it could help during the menopause transition.

While the concept of fasting has been around for centuries, scientific interest began to build in the 1990s. Its popularity really took off in 2012 with the release of the 5:2 diet, and since then, researchers have continued exploring its potential benefits — including for weight loss and blood sugar regulation.

But what exactly is intermittent fasting — and does the science support its use for women in midlife? Let’s take a closer look.

 

What Is Intermittent Fasting?

Intermittent fasting (IF) is an eating pattern that alternates periods of eating with periods of fasting.

Broadly speaking, there are two main types of intermittent fasting: alternate-day fasting and time-restricted eating (TRE).

Alternate-Day Fasting (ADF)

This approach involves eating normally on certain days and significantly reducing food on others — typically to around 500–800 calories on fasting days. One of the most well-known versions is the 5:2 method, where you eat as usual for five days of the week, and then choose two non-consecutive days to limit your intake. Other variations include eating just one meal a day or doing a true alternate-day fast, where you fast every other day.

Unlike time-restricted approaches, alternate-day fasting doesn’t require you to eat within a specific time window — the focus is more on how much you eat on the fasting days, rather than when.

Time-Restricted Eating (TRE)

Time-restricted eating, on the other hand, focuses on limiting the hours during which you eat each day — usually to a window of 4 to 10 hours, with the rest of the day spent fasting. The 16:8 method is perhaps the most popular, where you fast for 16 hours and eat all your meals within an 8-hour window (for example, from 12pm to 8pm). Some programmes go further, recommending shorter eating windows of 4–6 hours.

TRE is also tailored based on timing preferences:

• Early TRE involves starting your meals earlier in the day — say, beginning at 7am and finishing by mid to late afternoon.
• Late TRE begins later, often around noon, and finishes in the evening.

This approach gives the body a longer daily break from eating, and researchers have proposed several reasons why it might help.

TRE may help us eat in a way that’s more in sync with our body’s natural daily rhythm — the internal clock that follows the light and dark cycle — which plays a role in many areas of our health. It may also be that limiting the hours in which we eat could help reduce the likelihood of overeating by reducing snacking or eating opportunities.

We’ll explore what the current evidence says about IF and whether it may be a useful approach to consider in midlife.

 

 

 

Does Intermittent Fasting Really Help with Weight Loss? What the Science Says

Much of the early excitement about time-restricted eating (TRE) began with research in mice. Researchers fed the mice a high-fat diet and gave them constant access to food, which led them to gain weight — as you’d expect. But when they could only eat during a shorter window (about 8 hours), they lost weight, even though they ate the same number of calories as the mice eating all day. This weight loss was because they burned more energy than the mice eating all day (study).

Naturally, researchers grew interested in whether similar effects might occur in humans. But when they tested TRE in people, they didn’t find the same increase in energy burned. Several high-quality studies have shown that this specific mechanism doesn’t seem to translate from mice to humans (study & study) .

That said, this doesn’t mean TRE has no effect on weight in humans.

In fact, studies show that limiting the eating window to around 8 hours a day can lead to weight loss of around 3.5 to 4.5 kg (7–10 lbs) over 6 or more (study & study).

The likely reason? When we shorten the time we eat, we often eat less overall, even without deliberately restricting calories. Many people naturally reduce their energy intake simply because they have fewer opportunities to eat — and this seems to be the main way TRE supports weight loss in humans.

What about alternate-day fasting (ADF)?

Researchers studying people who followed the 5:2 diet for six months observed an average weight loss of 6.4 kg (study), which closely matches the results seen with ADF (study). In fact, reviews comparing the 5:2 diet, ADF, and TRE suggest there’s no clear winner in terms of effectiveness (study), although the findings aren’t entirely consistent.

 

How Does Intermittent Fasting Compare to Other Weight Loss Methods?

The short answer? It’s not necessarily more effective — but it can work just as well for some people, depending on their preferences and lifestyle.

When researchers directly compare intermittent fasting with more traditional daily approaches, they usually find similar results (study). Weight loss and health markers (like blood sugar) improve in both groups, with no consistent advantage for one over the other (study).

The only exception to this is early TRE when eating occurs early in the day often finishing by 3-5pm – in this instance metabolic markers like insulin sensitivity, blood sugar control and blood pressure are improved (study). This benefit is believed to result from aligning food intake with the body’s natural circadian rhythm and the light–dark cycle, as our bodies are more efficient at processing food earlier in the day compared to later in the evening. While adopting early TRE can be difficult due to modern lifestyle demands, simply shifting meals earlier and avoiding late-night eating may offer meaningful health advantages.

As with most things in nutrition, what works best tends to vary from person to person. Some people respond well to IF and find it easy to stick with. Others don’t see much change or find it doesn’t fit with their lifestyle. If it suits you and helps you stay consistent, it may be a useful strategy — but it’s not a magic fix.

 

What About Muscle Loss?

In midlife, preserving muscle while losing weight is especially important, because we naturally lose muscle as we age. The concern with any weight loss approach — including TRE — is whether the proportion of muscle lost is too high (study).

Most studies on TRE and ADF report that people lose about two-thirds of their weight as fat and one-third as muscle — a pattern similar to traditional diets. Some smaller studies suggest IF may cause slightly more muscle loss, but researchers have found limited evidence to support this.

Regardless of the approach you choose, protecting your muscle is key.

That means getting enough protein and including resistance or strength training at least 2–3 times a week. Adding in resistance training alongside IF has been shown to limit muscle loss (study and study) as well as being beneficial for all aspects of health in midlife and beyond.

 

 

 

Can Intermittent Fasting Help Reduce Our Waistline?

This is an important question for many midlife women, as we often notice more fat around our middle. This abdomen fat (visceral fat) is strongly linked to insulin resistance, inflammation, type 2 diabetes, and heart disease.

So can IF help reduce this kind of fat?

Yes research shows IF can reduce visceral fat — but not more than other weight loss approaches (study). The key factor is the weight loss itself, not necessarily the method used to achieve it. So, if IF supports weight loss for you, it may also help reduce internal fat stores associated with metabolic risk.

While many studies have included perimenopausal and postmenopausal women, very few have focused on the menopause transition specifically. This means we still have more to learn about how effective and/or appropriate time-restricted eating is during menopause.

One study found no difference in weight loss or its benefits in menopausal women although more research is needed.

In fact, research in people with fatty liver disease has shown that IF can significantly reduce liver fat but it isn’t a superior approach to other weight loss approaches (study).

 

Special Considerations for Women in Midlife

Before you start IF, take time to consider a few important factors.

Nutritional Needs in Midlife

Whatever approach you choose, make sure you’re getting the nutrients your body needs. Especially during perimenopause and postmenopause, when some become even more important.

• Fibre plays a key role in gut health and weight regulation. It also reduces the risk of chronic diseases that become more common with age.
• Protein is crucial for helping manage hunger and for preserving muscle mass. We naturally lose muscle in midlife, and weight loss can speed up that decline.
• Calcium and other bone-supporting nutrients are also vital, as menopause is a time of increased risk for bone loss. Aim for three servings of high-calcium foods each day to support bone health.

If your eating window is shortened, consider whether there’s enough time to meet these nutritional needs. It may be necessary to plan meals more intentionally to make it work.

 

 

Lifestyle Fit and Long-Term Sustainability

It’s also worth thinking about how IF would fit into your daily life. For example:

• How would this approach work alongside family meals or social events?
• Would a shortened eating window feel manageable day-to-day, or might it create added stress?
• Is it something you can realistically stick with over the long term?

Sustainability really matters — especially if this is your main approach to managing weight. If the pattern is too difficult to maintain, it may lead to weight regain once it’s no longer being followed.

Starting with a gentler version, such as a 12:12 or 14:10 TRE pattern may be a better approach. This gives you space to experiment while still supporting your nutritional needs and lifestyle.

 

Is Intermittent Fasting Right for You? Questions to Think Through

If you’re considering trying IF, take a moment to reflect on these questions before you begin:

• What would help me meet my nutritional needs within a shorter eating window?
• Could this approach fit comfortably into my current lifestyle and routine?
• Do I feel well — physically and mentally — when I go for longer periods without eating?
• Is this a pattern I can realistically maintain over the long term?
• Am I choosing this strategy from a place of self-care and curiosity, rather than pressure or guilt?

If you plan to try Intermittent Fasting During Menopause consider the following

• Start slow and experiment with eating windows to ensure you can eat all the important nutrients you need. If you’re eating for 15 hours a day then shortening this to 10-12 hours may be a helpful starting point.
• Focus on nutrient-dense, whole foods during eating periods.
• Stay hydrated.
• Talk with your doctor before fasting if you take medication for conditions like type 2 diabetes or high blood pressure.
• Track your progress — not just by weight, but by energy, sleep, and mood.

When Intermittent Fasting Might Not Be the Right Choice

Intermittent fasting can help some people, but it isn’t right for everyone. In some cases, it may do more harm than good.

• If you’ve had an eating disorder or disordered eating, fasting can trigger unhelpful patterns and is best avoided.
• Talk to your doctor before fasting if you take medications — especially for diabetes or high blood pressure. Fasting can affect blood sugar and dosing needs.
• If you’re feeling unwell or feeling overwhelmed with menopause symptoms, IF may not be the best option right now.

As always, listen to your body — and seek professional support if you’re unsure.

 

Final Thoughts: Is Intermittent Fasting Right for You?

Intermittent fasting — especially earlier time-restricted eating — may be a helpful tool for some women in midlife. It can support changes in weight and metabolic health. While it’s not a magic fix it may be effective if it fits your lifestyle and feels sustainable.

The key takeaway?

There’s no one-size-fits-all strategy.

Whether or not you try intermittent fasting, focus on what supports your body, health, and long-term wellbeing. Consider good nutrition, muscle and bone strength, stress management, and a routine that works for you.

If you’re curious about intermittent fasting, start gently, stay flexible, and listen to how your body responds. And if it’s not the right fit? That’s okay too — there are many ways to care for your health during and after menopause.

 

Frequently Asked Questions (FAQs)

Q: Is intermittent fasting safe for women in menopause?
A: There are few adverse effects reported in research. However, we still need more research on how it affects women in perimenopause and beyond. To minimise risk consider your nutritional needs, medications, and medical conditions. Speak with your doctor if you’re unsure.

Q: How long does it take to see results from intermittent fasting?
A: Changes in weight or energy take a few weeks but longer term results are seen at 3–6 months.

Q: Does intermittent fasting help with an expanding waistline?
A: IF can reduce abdominal fat, including visceral fat, but it’s not more effective than other approaches. The overall weight loss is what matters most in lowering visceral fat.

Q: Can intermittent fasting cause muscle loss?
A: IF can lead to muscle loss — but including sufficient protein and strength training can help minimise this.