Intermittent fasting is now a popular trend in the world of health and diet. This method not only helps to lose weight but also improves the body's metabolic patterns. For beginners, starting intermittent fasting can be a challenge. Here are some tips and tricks to get started easily and effectively.
What is Intermittent Fasting?
Intermittent fasting (IF) is an eating pattern that regulates when you eat, not what you eat. It involves regular cycles of eating and fasting, which has been shown to have a variety of health benefits based on recent scientific research. This means that you restrict your eating to a certain period, often with 16 hours of fasting and 8 hours of eating (16/8), or some other similar method.
Types of Intermittent Fasting Based on Evidence
1. Time-Restricted Eating (TRE) - Most Recommended
- 16:8 Method: Fast for 16 hours, eat within 8 hours
- 14:10 Method: Fast for 14 hours, eat within 10 hours
- Evidence: A 2024 study showed TRE had high-quality evidence for weight loss, fat loss, and improved insulin levels in overweight people.
2. Alternate Day Fasting (ADF)
- Fast completely or eat very little (25% calories) on alternate days
- Evidence: Effective for weight loss, but long-term compliance is more difficult
3. Modified Fasting (5:2)
- Eat normally for 5 days, limit calories to 500-600 calories for 2 days a week
- Evidens: High quality evidence for lowering LDL cholesterol
Scientifically Proven Benefits (Based on a 2024 Meta-Analysis)
- Effective Weight Loss
- IF is effective for weight loss and specific markers of cardiometabolic health in individuals with prediabetes or type 2 diabetes.
- Significant reduction in waist circumference and fat mass
- Metabolism Improvement
- Increased insulin sensitivity and fasting glucose levels
- Decreased systolic blood pressure
- Improvement of lipid profile (cholesterol)
- Heart Health
- IF can reduce waist circumference, fat mass, LDL-cholesterol, triglycerides, and increase HDL-cholesterol.
- Anti-Inflammatory Effects
- Reduction of inflammatory markers in the body
Worrying Cardiovascular Risks
A 2024 study of more than 20,000 adults found that those who followed an 8-hour restricted eating schedule had a 91% higher risk of dying from cardiovascular disease.
Vital Records:
- This research is still preliminary and has not been peer-reviewed.
- There is no information on diet quality, physical activity, or other lifestyle factors.
- Experts advise "don't panic" but remain vigilant
Common Side Effects (Based on 2024 Research)
- Adaptation Phase (first 1-2 weeks):
- Excessive hunger, headaches, fatigue, and mood changes
- Constipation and digestive problems
- Temporary energy drop
- Eating Behavior Risks:
- Tendency to binge eat after a period of fasting
- Obsession with food
- Eating disorders
- Hormonal Problems:
- Decreased reproductive hormones in women
- Menstrual cycle disorders
Impact on Bone Health - Key Findings:
A 2024 systematic review showed that TRE for up to 6 months had no adverse effects on bone and may even provide some protection against bone loss during modest weight loss.
But please note:
- IF may reduce physical activity more than other energy restriction methods, which may have negative effects on bone health.
- The combination of IF with exercise has been proven to be safe and feasible.
Who Shouldn't Do Intermittent Fasting?
Absolute Contraindications:
- Pregnant and breastfeeding mothers
- Children and teenagers (under 18 years old)
- People with type 1 diabetes
- History of eating disorders (anorexia, bulimia)
- People with severe kidney or liver failure
Need to Consult a Doctor:
- Type 2 diabetes (especially those using insulin)
- Hypertension with medication
- History of gallstones
- Elderly (over 65 years)
- People with GERD or chronic stomach ulcers
- People who must take medication with food
Combination with Sports:
- Research shows that moderate to high intensity exercise can be done during the fasting period.
- Light cardio during fasting (brisk walking, yoga)
- Resistance training should be done close to or after meal periods.
- Listen to your body - stop if you feel excessively weak.
Health Monitoring
- Routine check-up:
- Monthly weight and body composition
- Blood sugar, lipid profile every 3-6 months
- Weekly blood pressure (if there is a history of hypertension)
- Danger sign to stop:
- Weight loss >1kg/week
- Persistent sleep disturbance
- Mood swings or depression
- Menstrual cycle disorders in women
- Dizziness or fainting
Myths vs Facts Based on Science 2024
- MYTH: "IF slows down metabolism"
- FACT: IF can increase metabolism in the short term through metabolic switching from glucose to ketones.
- MYTH: "You can eat anything during the eating period"
- FACT: Food quality still matters - IF is not a license to eat junk food
- MYTH: "IF is definitely safe for everyone"
- FACT: There are contraindications and side effects to be aware of.
- MYTH: "The longer the fast, the better"
- FACT: Experts do not recommend eating only one meal a day.
Final Recommendations
IF Might Be Right for You If:
- Want to lose weight with a structured method
- Have a lifestyle that allows for a regular eating schedule
- Have no medical conditions that would prevent
- Can maintain nutritional quality during meal periods
Consider Alternatives If:
- Have a history of eating disorders
- Shift work or irregular schedules
- In a period of growth or recovery
- Experiencing excessive stress
Intermittent fasting, especially TRE, is a promising intervention for weight and metabolic health, particularly beneficial for adults with overweight or obesity.
However, recent findings on potential cardiovascular risks remind us that:
- Food quality remains the main priority
- Medical consultation is mandatory before starting
- Monitor your health regularly
- An individual approach is more important than following trends
Remember: IF is a tool, not a magic bullet. Long-term success still depends on an overall healthy diet, regular physical activity, and a balanced lifestyle.
Article written by dr. Yuliyana Kusaeri, M.Gizi, Sp.GK (Clinical Nutrition Specialist Doctor, EMC Cibitung & Pekayon Hospital).