Nate Kesterson
Benefits of Intermittent Fasting
Intermittent fasting has become an increasingly popular approach to health, weight loss, and disease prevention in recent years. More and more research is emerging showing the wide-ranging health benefits of intermittent fasting for overall wellness and prevention of chronic diseases.
In this detailed blog post, we will explore realistic and science-backed health benefits of intermittent fasting, plus provide tips for getting started.
1. Promotes Weight Loss
One of the most popular reasons people try intermittent fasting is to lose weight. By restricting the hours of the day when you eat, intermittent fasting can help reduce calorie intake and promote weight loss (1).
In one review study, people lost between 7-11 pounds of weight over a 10-week period by intermittent fasting (2). Other studies have shown that intermittent fasting is as effective for short-term weight loss as traditional calorie restriction (3).
Reduced calorie intake, lowered blood insulin levels, and increased fat burning all contribute to the weight loss effects of intermittent fasting (4). Intermittent fasting provides a structured approach to lower calorie intake which often results in weight loss, especially for those looking to lose 10 pounds or more.
2. Lowers Insulin Resistance
Intermittent fasting has been shown to improve insulin sensitivity and lower blood sugar levels (5). Insulin resistance is a major risk factor for developing type 2 diabetes.
By giving your pancreas a break from constantly producing insulin, intermittent fasting can help restore your body’s sensitivity to this important hormone (6). Studies have shown reductions in blood sugar levels and insulin resistance from intermittent fasting that were comparable to some diabetes medications (7).
3. Extends Lifespan
Animal studies have suggested that intermittent fasting may extend lifespan by as much as 30% (8). This remarkable anti-aging effect seems to be related to a reduction in insulin and blood sugar levels, as well as decreased inflammation from fasting (9).
While human data is limited, some small studies have shown intermittent fasting may help preserve muscle mass and brain function during aging (10). More research is needed, but intermittent fasting shows early promise for robust anti-aging effects beyond just simple weight loss.
4. Protects Against Cancer
Intermittent fasting has shown promising benefits for cancer prevention in animal studies (11).
One study found that intermittent fasting slowed breast cancer tumor progression in mice (12). Fasting seemed to make the cancer cells more sensitive to chemotherapy treatment.
While human studies are still needed, this indicates intermittent fasting may help complement conventional cancer therapies. The fasting state may weaken cancer cells while protecting normal cells (13).
5. Boosts Brain Health
Intermittent fasting has been shown to boost a brain hormone called BDNF, which promotes the growth of new neurons and protects brain cells from degeneration (14).
Animal studies have found intermittent fasting protected against stroke damage and Alzheimer’s disease (15, 16). One study found that intermittent fasting for 12 months improved verbal memory scores in healthy older adults (17).
More research is needed, but intermittent fasting appears to provide impressive boosts to multiple aspects of brain health beyond just weight management.
6. Provides an “Eating Curfew”
One unique benefit of intermittent fasting is that it can provide a natural “eating curfew” and cut down on late night snacking.
By restricting the hours for eating, intermittent fasting can reduce the temptation to eat late at night after dinner. This helps avoid “mindless overeating” and consuming excess calories when they are less likely to be burned off (18).
Research confirms that consuming more of our calories in the evening is associated with higher body fat percentages (19). So intermittent fasting can help curb this tendency to snack into the late hours.
7. Allows Inclusion of Favorite Foods
One great thing about intermittent fasting is that it does not restrict which foods you can eat, just when you can eat them. This allows you to still enjoy some of your favorite foods in moderation (20).
As long as you are mindful of nutrition and portion sizes, intermittent fasting provides flexibility in your eating plan. This makes it a sustainable lifestyle that can include foods you love without the need to eliminate entire food groups.
8. Physical Benefits
Suppresses Inflammation
Chronic inflammation is closely linked to many diseases and accelerated aging processes in the body (21). When cells are under stress or irritated, they release pro-inflammatory cytokines and acute phase proteins like C-reactive protein (CRP) into the bloodstream. While acute inflammation is a normal healthy response, chronic systemic inflammation can be problematic and damage healthy tissue over time.
Markers of inflammation such as CRP, interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) have all been shown to decrease through intermittent fasting regimens (21, 27).
One study found that an alternate-day fasting plan for 12 weeks decreased CRP by 43% and IL-6 by 57% (28). This reduction of inflammatory markers may be tied to concurrent weight loss and improvements in insulin resistance that often accompany intermittent fasting.
The anti-inflammatory effects of fasting may help explain some of the beneficial outcomes on conditions like arthritis, asthma, multiple sclerosis, and inflammatory bowel disease (29). More research is still needed, but evidence indicates intermittent fasting can be an effective dietary strategy to lower systemic inflammation and protect against inflammation-related diseases.
Chronic inflammation is linked to many diseases and aging processes. Markers of inflammation such as C-reactive protein (CRP) are reduced through intermittent fasting (21). This anti-inflammatory effect may be tied to weight loss and lowered insulin resistance.
Increases Growth Hormone
One exciting benefit of intermittent fasting is that it can naturally boost growth hormone production during the fasting periods, especially for men (22). Growth hormone is an anabolic hormone made in the pituitary gland that promotes fat burning and muscle building when released.
During short-term fasting, studies have shown spikes in growth hormone levels of up to 300-400% (30). This fasting-induced surge in growth hormone works synergistically with other fasting hormones like norepinephrine to ramp up lipolysis and break down fat stores for energy (31).
For those looking to get lean, intermittent fasting can skyrocket growth hormone to accelerate the fat loss results from the calorie deficit.
In addition to fat burning, increased growth hormone from fasting may preserve or even build muscle mass despite being in a calorie deficit. By inhibiting protein breakdown and stimulating muscle protein synthesis, growth hormone counteracts the loss of muscle that typically occurs when losing weight (32).
This makes intermittent fasting an intriguing strategy not only for fat loss but for anti-aging effects and body recomposition.
Boosts Cellular Repair
When fasting, cells initiate enhanced repair processes like autophagy to recycle damaged proteins and organelles (23). This cleansing effect helps cells function optimally. Intermittent fasting activates these repair pathways.
Lowers Blood Pressure
By lowering insulin levels, intermittent fasting can reduce sodium retention and blood pressure (24). Many people with high blood pressure find intermittent fasting helps lower their blood pressure readings.
Improves Gut Health
During the fasting periods, gut cells initiate a cleansing process and recycle old components (25). Intermittent fasting may even help combat leaky gut syndrome by giving the gut lining a rest.
Enhances Cardiovascular Function
Animal studies suggest intermittent fasting may improve cardiovascular risk factors and blood flow by enhancing the function of the endothelium cells that line the blood vessels (26). More research is needed to confirm benefits for heart health.
Bonus: It’s Simple and Easy to Follow
Unlike many diets and eating plans, intermittent fasting does not require you to calculate calories, weigh food portions, or meticulously track everything you eat. You simply focus on the time period when you can eat and fast the rest of the time.
This simplicity makes intermittent fasting a straightforward and sustainable approach for the long-term.
You don’t need to stress about every bite of food, just sticking to your selected feeding window. So intermittent fasting offers many of the benefits of dieting without most of the tedious work required.
Tips for Getting Started with Intermittent Fasting
If you want to try intermittent fasting, here are some tips to get started:
- Consult your healthcare provider, especially if you have any medical conditions or take medications.
- Start with easier fasting schedules like 12-14 hours and work your way up.
- Water should be your primary beverage, but unsweetened tea and black coffee can also be part of your fasting fluid intake.
- Focus your meals around protein, fiber, and healthy fats to feel satisfied.
- Take electrolytes like magnesium if you feel low energy or headaches.
- Exercise as normal, but consider easy workouts during fasts.
- Rest well and manage stress levels to avoid burnout.
Conclusion
Intermittent fasting is a tool that offers many evidence-based health benefits for weight loss, blood sugar regulation, cancer prevention, brain function, and longevity.
By providing a natural eating curfew and flexibility with food choices, intermittent fasting is a simple, sustainable approach to improving health.
Experiment with different intermittent fasting schedules to find one that fits your lifestyle. Be sure to discuss any new diet plans with your doctor, especially if you have any underlying health conditions.
With some patience to adapt, intermittent fasting can be an easy way to boost your overall wellbeing through multiple mechanisms.
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