For the past decade or so, intermittent fasting (IF) has taken both the fasting and fitness communities by storm. Combined with exercise i.e cardio and strength training, the various types of intermittent fasting have been claimed to be quite effective in weight loss and other health benefits.
Intermittent fasting 19/5 is one of the many schedules that many on this diet follow. While it is not as popular as the beloved 16/8 plan, 19/5 intermittent fasting benefits seem to be similar to other IF plans.
Read on to learn more about what fasting 19 hours a day can potentially do to your body and overall health, how much weight you might expect to lose, what you should and shouldn’t eat, and much more!
What Is Intermittent Fasting 19/5?
This is a time-restricted eating strategy where you fast for 19 hours a day and only have a 5 hour eating window. In this 19/5 fasting schedule you need to consume all your allocated calories for the day in this 5-hour window.
This can be done in one large meal, or several small meals and snacks sprinkled throughout this feeding/eating window. The 19/5 fasting method is certainly more advanced than the 16/8 method but slightly easier than 20/4 or the OMAD (One Meal A Day) diet.
Is It Okay To Fast 19 Hours A Day?
Yes, it is.
According to Medical News Today, it is relatively safe for most healthy adults to go a full 24 hours a day without food (21). A 19 hour fast is shorter than the full 24 hours, so many people can safely go without food without any major side effects.
Reasons why BetterMe is a safe bet: a wide range of calorie-blasting workouts, finger-licking recipes, 24/7 support, challenges that’ll keep you on your best game, and that just scratches the surface! Start using our app and watch the magic happen.
With that said, despite its relative safety and benefits, not everyone should hop on the intermittent fasting trend. Groups of people who should keep away from IF include:
Children and teenagers
They go through periods of rapid growth. Food is essential in growth spurts and restricting it may lead to unwanted side effects. A study published in 2014 stated that growth spurts increase nutritional needs of both macro and micronutrients.
A higher calorie intake as well as more protein, iron, calcium, zinc and folate are required during this time. Failure to get enough calories as well as vitamins and other nutrients during such a time could derail and delay the growth spurt or even puberty (20).
Pregnant women and breastfeeding mothers
According to UNICEF, poor nutrition during pregnancy may lead to anemia, pre-eclampsia, hemorrhage and death in mothers. It could also lead to stillbirths, low birthweight, wasting and developmental delays for children (19).
In breastfeeding women, intermittent fasting may lead to decreased breast milk production (8), fatigue and dehydration.
Even if a breastfeeding woman could ensure that she eats all her required calories and nutrients during the feeding window, a combination of IF plus all the fatigue a new mother goes through as well as other life factors might make this hard if not impossible.
People with insulin-dependent diabetes
Intermittent fasting with insulin-dependent diabetes puts you at a risk of your blood sugar dropping too low, which significantly increases the risk of acute diabetes complications like hypoglycemia and significant hyperglycemia.
While some studies claim that with education and daily advanced glucose monitoring people with uncomplicated type 1 diabetes could fast safely (14), we suggest that you just not do it altogether. As they say it, better safe than sorry. Even if you have type 2 diabetes and are not on insulin, it is crucial to speak to your healthcare provider before starting a fasting regimen, as you are also at risk of low blood sugar events. The same advice goes for anyone else on medication that can lower their blood sugar.
Anyone with a history of an eating disorder history
In an article published earlier this year in Psychiatric News earlier this year, IF is associated with a higher risk of eating disorders as well as eating disorder behaviors in both adolescents and young adults (15).
- All eating disorder behaviors – i.e. overeating, binge eating, vomiting, laxative use, compulsive exercise, and fasting – as well as higher EDE-Q (Eating Disorder Examination Questionnaire) global scores in women.
- Compulsive exercise, fasting, and higher EDE-Q scores in men. Vomiting was associated with fasting in the last 30 days but not 12 months.
- Higher EDE-Q scores in transgender/gender nonconforming people
What Are The Benefits Of The 19 Hours A Day Fast?
Intermittent fasting 19/5 probably has similar benefits to all other IF schedules, namely the 16:8, 14:10, 12:12, 20/4, the 5:2 diet, as well as OMAD. These benefits might include:
- Aid fat weight loss – Intermittent fasting 19/5 weight loss is probably the main reason why most people look into this eating cycle.
Intermittent fasting can help with weight loss by helping you to eat fewer calories overall, without calorie counting or restricting your diet.
A review of 27 studies published in the Canadian Family Physician journal in 2020 found that various methods of intermittent fasting helped participants lose 0.8 percent to 13 percent of their baseline body weight (13).
- Lower risk of Type 2 Diabetes – In 2014, a study published in Translational Research concluded that daily intermittent fasting and alternative day IF (like the 5:2 diet), might not only be used as alternatives to daily calorie restriction for weight loss but also as a means to improve insulin sensitivity (17).
In a recent study published in 2022, researchers found that intermittent fasting helped lower fasting blood sugar by an average of 0.15 millimoles per liter, as well as lowering other markers of insulin resistance. The researchers concluded that IF might be used as an auxiliary treatment to prevent the occurrence and development of chronic diseases (3).
Remember that better insulin sensitivity and blood sugar levels not only help prevent diabetes, but are essential in the management of type 2 diabetes.
- Improved heart health – Studies on intermittent fasting show that it may help reduce blood sugar levels, total cholesterol, triglycerides and lower blood pressure, all factors that increase the risk of heart disease (10, 2).
- Improved brain health and protection against neurodegenerative diseases – In a study published in Nutrients in 2022, researchers stated that IF may induce several molecular and cellular adaptations in neurons, which, overall enhance cellular stress resistance, synaptic plasticity, and neurogenesis (4).
In a review published earlier this year, researchers concluded that long term intermittent fasting might potentially reverse or delay the pathological process in Alzheimer’s disease (5).
- Reduced oxidative stress and inflammation in the body – These two factors accelerate aging, and increase your risk of common and chronic illnesses (9, 1).
Intermittent fasting has also been claimed to help improve your sleep and reduce brain fog, improving focus, mental clarity and reducing forgetfulness and confusion (7).
How Much Weight Can I Lose If I Fast 19 Hours A Day?
The number varies from person to person.
However, safe and sustainable weight loss is characterized by losing 1 to 2 pounds a week, which translates to losing about 4 to 8 pounds a month (18).
As seen above, intermittent fasting can lead to weight loss through calorie restriction (eating less hours can translate to eating less overall).
You can also boost your weight loss by adding a workout plan to your intermittent fasting. Exercise increases calorie burning and increases lean mass, which also boosts resting metabolic rate – i.e you burn more calories while at rest.
Which Is The Best Intermittent Fasting Schedule For Women?
The best intermittent fasting schedule is the one that works best for you. No schedule is better for women but not men and vice versa.
19/5 fasting for women can work if the women in question stick to it and follow the rules on what to and what not to eat or drink during the fasting and eating windows. Shorter or longer fasts will work and elicit the same benefits as long as you are consistent and stick to the rules. That said, women may need to adjust their fasting schedule based on how their bodies feel due to fluctuations in hormones over their menstrual cycles, which can affect energy levels. It’s important to listen to your body and be kind to it. Some women, such as those who are pregnant, trying to conceive, or breastfeeding, should not practice intermittent fasting.
What Is Intermittent Fasting By Age?
This is a new fad that people are using to try and capitalize on the intermittent fasting for weight loss trend. These people claim that some schedules work better for certain age groups and can help them lose more weight. This, however, seems to be false and a scam that has no scientific backing to it.
As stated above, the best IF schedule for you is what you have tried and find easiest to do/follow.
As long as you don’t consume anything that will break your fast during the fasting window, and eat nutritious foods that are within your allocated daily calorie intake during the feeding window, you are likely to not only lose weight, but also experience the above mentioned health benefits.
BetterMe app will provide you with a host of fat-frying fitness routines that’ll scare the extra pounds away and turn your body into a masterpiece! Get your life moving in the right direction with BetterMe!
What Should I Eat When Intermittent Fasting 5 Days A Week?
Most time-restricted feeding regimens aim for intermittent fasting all 7 days of the week. This is unless you are following the 5:2 diet which involves eating as usual 5 days a week and drastically cutting your calorie intake to 500 or 600 calories (for women and men, respectively) on two non-consecutive days of the week. Or alternate-day fasting, which, as it sounds, consists of fasting every other day.
During the fasting window you are not allowed to eat or drink anything that can break your fast. Food will obviously break your fast, but drinks that will not break your fast include:
- Plain or sparkling water (unsweetened)
- Unsweetened tea (green, black, herbal, etc.) or coffee with no sugar or creamer
Once your eating window starts, make sure to eat a healthy, balanced diet and stick to your recommended calorie deficit intake for weight loss. While some claim that you can still eat whatever you want during this window and still lose weight, the process will likely take longer and overeating unhealthy foods could lead to health issues.
The best intermittent fasting diet should
- Include large amounts of a variety of fruits and vegetables
- Have protein rich foods – Both animal and plant based sources, unless you prefer a plant-based diet. Protein is great for muscle building and maintenance.
- Include complex carbohydrates – They help boost satiety, digestion and give you strength to not only get through your day but also survive all 19 hours.
- Be rich in healthy fats
- Avoid high added sugar, high sodium and well as overly processed foods
Read more: What Can I Eat During Intermittent Fasting?
The Bottom Line
Intermittent fasting 19/5 may not be listed among the main IF schedules, but it is still a schedule, nonetheless. This schedule is for those who may have been doing the 16:8 and want to push their bodies further, but are not quite ready to tackle the 20:4.
If you choose to do the 19/5 schedule, be sure to stay as hydrated as possible during the fasting window to avoid dehydration. Once the eating window opens up, be sure to fill up on quality protein, complex carbs, healthy fats, and lots of vegetables. Talk to your healthcare provider before starting a fasting regimen, especially if you have any medical conditions or are taking any medications.
This article is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional advice or help and should not be relied on to make decisions of any kind. Any action you take upon the information presented in this article is strictly at your own risk and responsibility!
- Dietary Intake Regulates the Circulating Inflammatory Monocyte Pool (2019, cell.com)
- Effect of Epidemic Intermittent Fasting on Cardiometabolic Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials (2021, pubmed.ncbi.nlm.nih.gov)
- Effect of Intermittent Fasting Diet on Glucose and Lipid Metabolism and Insulin Resistance in Patients with Impaired Glucose and Lipid Metabolism: A Systematic Review and Meta-Analysis (2022, ncbi.nlm.nih.gov)
- Effects of Intermittent Fasting on Brain Metabolism (2022, ncbi.nlm.nih.gov)
- Effects of intermittent fasting on cognitive health and Alzheimer’s disease (2023, ncbi.nlm.nih.gov)
- Effects of Intermittent Fasting on the Circulating Levels and Circadian Rhythms of Hormones (2021, ncbi.nlm.nih.gov)
- Health benefits of intermittent fasting (and tips for making it work) (2021, uclahealth.org)
- How do pregnant and lactating women, and young children, experience religious food restriction at the community level? A qualitative study of fasting traditions and feeding behaviors in four regions of Ethiopia (2018, ncbi.nlm.nih.gov)
- Impact of intermittent fasting on human health: an extended review of metabolic cascades (2018, tandfonline.com)
- Intermittent Fasting: A Heart Healthy Dietary Pattern? (2020, ncbi.nlm.nih.gov)
- Intermittent fasting: Describing engagement and associations with eating disorder behaviors and psychopathology among Canadian adolescents and young adults (2022, pubmed.ncbi.nlm.nih.gov)
- Intermittent Fasting and Metabolic Health (2022, ncbi.nlm.nih.gov)
- Intermittent fasting and weight loss (2020, ncbi.nlm.nih.gov)
- Intermittent Fasting Could Be Safely Achieved in People With Type 1 Diabetes Undergoing Structured Education and Advanced Glucose Monitoring (2019, ncbi.nlm.nih.gov)
- Intermittent Fasting Linked to Eating Disorder Behaviors (2023, psychnews.psychiatryonline.org)
- Intermittent Fasting Promotes Fat Loss With Lean Mass Retention, Increased Hypothalamic Norepinephrine Content, and Increased Neuropeptide Y Gene Expression in Diet-Induced Obese Male Mice (2016, ncbi.nlm.nih.gov)
- Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings (2014, pubmed.ncbi.nlm.nih.gov)
- Losing Weight (2023, cdc.gov)
- Maternal nutrition (n.d., unicef.org)
- Nutrition and pubertal development (2014, ncbi.nlm.nih.gov)
- What happens if you fast for a day? (2023, medicalnewstoday.com)