By Dr.Ryan Yanez
Intermittent fasting has become one of the most talked-about health trends in the last decade. From fitness influencers to physicians, many people claim that restricting when you eat can improve weight loss, metabolic health and even longevity.
The potential benefits of intermittent fasting may depend not only on when people eat, but also on what they choose to eat during those eating windows.
Two weeks ago, I – your trusted wellness chiropractor in Troy, MI – decided to try intermittent fasting myself. Rather than just following online advice, I started reviewing the latest scientific evidence on the topic. One of the most comprehensive analyses I came across was a 2025 large systematic review and network meta-analysis of randomized clinical trials examining different intermittent fasting strategies and their impact on body weight and cardiometabolic risk factors.
How Does Intermittent Fasting Actually Affect Weight Loss and Metabolic Health?
The research study that I reviewed suggests that intermittent fasting can be an effective tool for weight management and metabolic health. However, the evidence also indicates that fasting is not necessarily more effective for weight loss than traditional calorie restriction.
What is intermittent fasting?
Intermittent fasting (IF) is not a traditional diet. Instead of focusing primarily on what you eat, it focuses on when you eat.
This study looked at three popular intermittent fasting methods:
• Time-Restricted Eating (TRE): Eating within a limited window each day, typically 16 hours fasting and 8 hours eating.
Example schedule: Eat between 12:00 PM and 8:00 PM, fast the remaining 16 hours.
• Alternate-Day Fasting (ADF): Alternating between one day of normal eating and one day of significant calorie restriction or fasting.
• The 5:2 Method: Eat normally for five days each week and restrict calories significantly on two non-consecutive days.
Most beginners start with time-restricted eating, which is what I’m currently experimenting with.
What the Latest Research Examined
The recent meta-analysis I reviewed is one of the most comprehensive evaluations of intermittent fasting so far (BMJ 2025;389:e082007). The findings were fascinating and a bit more nuanced than the typical headlines.
Researchers analyzed:
- 99 randomized clinical trials
- More than 6,500 adult participants (720 healthy, 5,862 existing health conditions, with a median BMI of 31.0, which is in the obese category)
- Multiple fasting approaches compared with traditional calorie-restricted diets and unrestricted eating.
The goal was to understand how intermittent fasting affects:
- Body weight
- Blood pressure
- Cholesterol levels
- Blood sugar markers
- Overall cardiometabolic health
Because it combines results from many studies, this type of research provides a broader and more reliable perspective than a single clinical trial.
Key finding from the study: Alternate-day fasting produced the best results
In particular, alternate-day fasting was associated with reductions in weight loss, total cholesterol, triglycerides and non-HDL cholesterol.
Among the different fasting strategies studied, alternate-day fasting produced slightly greater weight loss than continuous calorie restriction. On average, participants lost about 1.3 kg (around 2.9 pounds) more than those following standard calorie-cutting diets. While statistically significant, this difference is relatively small, suggesting that the most effective diet may ultimately be the one people can sustain long term.
Why Intermittent Fasting Works
There are complex explanations involving insulin levels, cellular repair processes and "metabolic switching". However, the most practical explanation may be simple: a smaller eating window often leads to fewer calories consumed.
In other words, intermittent fasting may work less because of unique metabolic effects and more because it makes calorie control easier for some people. That doesn’t diminish its value. For individuals who struggle with traditional dieting, intermittent fasting can provide a structured and sustainable alternative.
My Experience After Two Weeks of Intermittent Fasting
Two weeks is obviously far too early to evaluate health outcomes, but I’ve noticed a few interesting behavioral changes.
What was easier than expected:
• Skipping breakfast became easier after the first few days.
• Hunger tends to come in waves and passes quickly.
• I’m more conscious of when I eat out of habit rather than hunger.
What was more challenging:
• Avoiding late-night snacking.
• Navigating social eating schedules.
The first few days of adjusting to longer fasting windows.
Final Thoughts
The data confirms that intermittent fasting is a fantastic tool for managing your weight and boosting your metabolic health. Just keep in mind that it’s not a magic bullet—the evidence shows it yields very similar weight loss results to simply cutting calories the traditional way.
One notable limitation of the review is the lack of detail regarding caloric intake during eating periods. Given that the median BMI of participants fell within the obese range and nearly 90% had existing chronic conditions, it is reasonable to infer that overall caloric intake may have remained relatively high. This highlights an important point: the potential benefits of intermittent fasting may depend on what they choose to eat during the eating windows.
Two weeks into the experiment, I’ve adjusted my approach to emphasize higher-quality, lower-calorie foods and I’m interested to see how things develop over the coming months.
Ready to take a holistic approach to your health, nutrition and wellness journey? Give Semlow Chiropractic a call today at (248) 879-8144 to schedule a consultation and see how we can support your goals.