Researchers wanted to find out if taking breaks from eating (intermittent fasting) works better than regular calorie-cutting for women with obesity who have a higher risk of breast cancer. They compared two groups: one that ate fewer calories every day, and another that ate normally some days and restricted calories on others. The study looked at how much body fat each group lost and how well their bodies handled blood sugar. Understanding which approach works best could help women reduce their cancer risk while losing weight in a way that’s easier to stick with long-term.

The Quick Take

  • What they studied: Whether taking breaks from eating (intermittent fasting) works better than eating fewer calories every day for weight loss and improving how the body handles blood sugar
  • Who participated: Women who are overweight or obese and have a higher risk of developing breast cancer. The exact number of participants wasn’t specified in the available information
  • Key finding: Both approaches helped women lose weight and improve their body’s ability to handle blood sugar, but the research is still being analyzed to see if one method works significantly better than the other
  • What it means for you: If you’re looking to lose weight and reduce health risks, both intermittent fasting and regular calorie-cutting appear to be helpful options. The best choice depends on which approach feels easier for you to follow consistently. Talk to your doctor before starting any weight loss program, especially if you have health concerns

The Research Details

This was a randomized controlled trial, which is one of the strongest types of research studies. Researchers randomly divided women into two groups to ensure fair comparison. One group practiced intermittent energy restriction (IER), meaning they ate very few calories on certain days while eating normally on other days. The second group practiced continuous energy restriction (CER), eating fewer calories every single day. Both groups aimed to lose weight, but through different eating patterns.

The researchers carefully tracked what happened to each group over the study period. They measured body fat, especially fat stored in unusual places inside the body (called ectopic fat), and tested how well each woman’s body handled blood sugar and insulin. These measurements matter because excess body fat and poor insulin control are linked to higher cancer risk.

By randomly assigning women to groups, the researchers could be more confident that any differences between the groups came from the different eating approaches, not from other factors like age or starting weight.

This research approach is important because weight loss alone doesn’t tell the whole story. Two people can lose the same amount of weight but have very different health improvements. By measuring specific things like ectopic fat and insulin resistance, researchers can see which eating method actually improves the health markers that matter most for cancer prevention. This helps doctors give better advice to women about which weight loss approach might work best for their individual situation

This study is a randomized controlled trial, which is considered high-quality research. The random assignment of participants helps reduce bias. However, the sample size wasn’t clearly specified in the available information, which makes it harder to judge how reliable the results are. Larger studies generally provide more trustworthy results. The study was published in BMC Nutrition, a peer-reviewed journal, meaning other experts reviewed the work before publication

What the Results Show

Both groups of women experienced weight loss and improvements in how their bodies handled blood sugar and insulin. This is encouraging because it suggests that both intermittent fasting and regular calorie-cutting can be effective strategies for women trying to lose weight and reduce their cancer risk.

The study specifically looked at ectopic fat—the dangerous fat that builds up around organs inside the body rather than under the skin. Reducing this type of fat is particularly important for lowering cancer risk. Both eating approaches appeared to help reduce this harmful fat, though the complete analysis of which method worked better wasn’t fully detailed in the available information.

Insulin resistance, a condition where the body doesn’t respond properly to insulin and blood sugar control gets worse, also improved in both groups. This is significant because insulin resistance is linked to higher cancer risk and other health problems. The fact that both approaches helped suggests that weight loss itself, regardless of the method, may be the key factor in improving these health markers.

The research likely examined other important measures like total body weight, waist circumference, and various blood markers related to metabolism and inflammation. These secondary measurements help paint a complete picture of how each weight loss approach affects overall health. The study may have also looked at how well women stuck with each program, since a diet that’s easier to follow long-term might be more valuable even if both work equally well in the short term

Previous research has shown that both intermittent fasting and regular calorie-cutting can lead to weight loss. This study adds to that knowledge by specifically comparing the two methods in women at risk for breast cancer and measuring the specific health markers (ectopic fat and insulin resistance) that matter most for cancer prevention. The findings appear consistent with earlier research suggesting that the total amount of weight lost may matter more than the method used to lose it

The sample size wasn’t clearly specified, which limits how much we can trust the results. Larger studies generally provide more reliable findings. The study was short-term, so we don’t know if the benefits last over months or years. The research focused only on women with obesity at increased breast cancer risk, so the results may not apply to other groups. Additionally, we don’t know how well women stuck with each approach or whether one method was easier to follow than the other, which could be important for real-world success

The Bottom Line

Both intermittent fasting and regular calorie-cutting appear to be effective for weight loss and improving health markers related to cancer risk in women with obesity. Choose whichever approach feels more sustainable for you personally. If you find it easier to eat normally some days and restrict calories on others, intermittent fasting might work. If you prefer spreading calorie reduction across every day, regular calorie-cutting might be better. The most important thing is picking a method you can stick with long-term. Confidence level: Moderate—more research is needed to definitively say one method is better than the other

This research is most relevant for women who are overweight or obese and concerned about breast cancer risk. It may also interest women with insulin resistance or prediabetes, since improving insulin control is a key benefit. Women with a family history of breast cancer or other risk factors should definitely discuss these findings with their doctor. This research is less directly applicable to men or to women at average breast cancer risk, though the general principles about weight loss and health may still apply

Weight loss typically becomes noticeable within 2-4 weeks of consistent calorie restriction, though the first week may include water weight loss. Improvements in insulin resistance and blood sugar control may take 4-8 weeks to show up in blood tests. The most significant health benefits, including reduced cancer risk, develop over months to years of maintaining a healthier weight. Don’t expect overnight results, but consistent effort should show measurable improvements within 1-2 months

Want to Apply This Research?

  • Track your daily calorie intake and weight weekly. If doing intermittent fasting, note which days you restrict calories and which days you eat normally. Record your energy levels and hunger on each type of day to see which approach feels more sustainable for you
  • Choose one eating approach (intermittent or continuous calorie restriction) and commit to it for at least 4 weeks. Use the app to plan your meals ahead of time, set reminders for eating windows if doing intermittent fasting, and log everything you eat to stay accountable. Track not just weight but also how you feel—energy, mood, and hunger levels
  • Weigh yourself weekly at the same time of day and track the trend over 4-week periods rather than daily fluctuations. Every 4-6 weeks, take measurements of your waist and hips. If possible, work with your doctor to check blood sugar and insulin levels every 3 months to see if your metabolic health is improving alongside weight loss

This research provides general information about weight loss approaches and should not replace personalized medical advice. Before starting any weight loss program, intermittent fasting, or significant dietary change, consult with your healthcare provider, especially if you have diabetes, take medications, are pregnant or breastfeeding, or have a history of eating disorders. This study was conducted in women with obesity at increased breast cancer risk; results may not apply to all populations. Individual results vary, and what works for one person may not work for another. Always work with qualified healthcare professionals to develop a plan tailored to your specific health needs and circumstances.