I used to be a doubting Thomas about intermittent fasting. I’m writing this as penance to correct questionable counsel I gave patients thousands of times
By Rafael Castillo M.D.
It started as a gesture of empathy.
A few weeks into the pandemic, with many reported to be starving, my wife and I thought it would be good to feel also what others had to struggle with—making do with just one, or at best, two meals a day, and dealing with the symptoms, like grumbling stomachs, dizziness and headaches due to hypoglycemia (low blood sugar levels).
It required some adjustments in our eating routine. Although I usually skipped lunch previously at work, I would have a heavy breakfast, a 4 p.m. snack and a late heavy dinner.
We canceled our breakfast, and reset our lunch to a late lunch, around 2 p.m. (which I occasionally stretch up to 6 p.m.) and just have one egg and fruits an hour before bedtime.
Essentially it’s intermittent fasting, eating nothing solid for 16 to 20 hours, and just taking in food in a four- to eight-hour period. But during the fasting period, I would have two cups of black coffee, three glasses of plain tea, a glass of carrot juice and around a liter of water.
Initially, when my stomach grumbled, I would drink a glass of water, and that sort of tricked my stomach into thinking that I took something, and the grumbling would stop. After a few weeks, my stomach had adjusted well to the new eating schedule, and was completely at peace with it.
The headaches and lightheadedness were quite a challenge in the first few weeks, but just like my stomach, my other organs apparently adjusted later on, and I could go on a longer fast beyond 20 hours, if not for the importuning of my wife and our cook that the food was getting cold at the table, and the ants were starting to feast on it.
What started as a sacrifice yielded palpable benefits, so we decided to continue doing it.
I lost around 18 pounds in seven months. I wasn’t really overweight; in fact, I had a lean frame, but my abdominal fat, a good indication of my sweet tooth, was disproportionately bulging. From a size 36 waistline, it’s down to 32 inches.
I used to take three antihypertensive pills. Now, my blood pressure is well controlled with just one pill.
My blood sugar was mildly elevated, and I had to take an antidiabetic agent. My glycated hemoglobin (HbA1c), which is an indication of the previous three-month blood sugar levels, is down from 6.5 percent to 5.3 percent. I’ve reduced my antidiabetic pill, and if the blood sugar holds, I might stop it completely.
My blood cholesterol levels have also never been this good. Despite my one-egg daily regimen, my good cholesterol increased to ideal levels, my bad cholesterol is down to very low levels, and my serum triglycerides are also well within normal limits. I have already reduced my dose of statin, my maintenance medicine for cholesterol.
Subjectively, I think my brain function has also improved. Whereas before, I would fall asleep after reading one or two pages of scientific journals (hence, it was my sleep-inducing pill), now, I can finish reading several articles before feeling sleepy.
My wife Becky, who’s the more conscientious health buff, says she notes similar benefits as I have. And it’s really consistent with what’s reported in the literature.
I used to be a doubting Thomas about intermittent fasting (IF), mainly because of the age-old belief and injunction that we should eat breakfast like a king, lunch like a rich man and dinner like a pauper. Now, apparently, that was one of the questionable counsels I gave my patients thousands of times over the 35 years of my clinical practice. I’m writing this as penance to correct that.
Although more studies are needed in humans, most of the current research in humans and experimental animals show consistently the beneficial effects on the body’s metabolism: better cellular and organ function, including that of the brain, heart and kidneys; prevention of cardiometabolic diseases like diabetes, elevated cholesterol levels and high blood pressure; possible prevention of Alzheimer’s and Parkinson’s disease; and enhanced longevity.
Many of the benefits of IF can be attributed to changes in hormones, expression of our genes and functioning of our cells. Yes, we’re not stuck to what kind of genes we have; its final expression may vary, depending on the internal and external environment the genes are exposed to. So, one may have the gene predisposing him to a certain cancer, but if the hormonal (internal) environment plus the external environment (lifestyle) are favorably modified, the chance of the individual developing cancer is significantly reduced, and the cancer may not express or manifest at all. Because of the favorable hormonal effects IF has been shown to produce, the cells in our body also initiate important cellular repair processes.
More effective than keto
Another benefit of IF is the reduction of inflammation in the body. We may not be aware of it, but because of the so-called oxidative stress we get from the environment (air pollution, smoking, unhealthy lifestyle, stress, etc.), there’s an insidious process of inflammation or swelling taking place at the cellular level, causing the early degeneration of our organs, subsequently leading to disease and premature death.
Data is now fairly robust that IF can effectively reduce oxidative damage and inflammation in the body, which can favorably impact against aging and development of the common lifestyle diseases, like cancer, heart, lung and brain diseases.
Maintenance of brain function to prevent dementia, Alzheimer’s and Parkinson’s disease should be an appealing motivation for the middle-aged and seniors to try IF. The shift in metabolism from utilizing glucose, which is not really the best source of energy, to ketones, which is a more efficient energy source, is one of the major reasons for the many benefits of IF. IF can increase ketone levels much more effectively than a ketogenic diet.
The body’s metabolism starts shifting to ketones after 12 hours of fasting, and this is enhanced further by the 16th hour and onward.
Talk to your doctor
So, should you go into IF?
As a general rule, I would say it’s beneficial for most, but it’s best to consult your physicians first if you have health issues like diabetes and heart disease, and are taking medicines for it. You have to be closely supervised, and blood levels of certain parameters may need to be monitored to guide your doctor in the adjustment of your medicines.
These health issues only require some monitoring precautions, but they are not contraindications to IF. In fact, IF may help partly control or treat these health problems, making possible a reduction in the doses of your medicines.
Sustaining IF requires a strong will. Many give up in the first few weeks because of the symptoms they feel. Rather than give up altogether, I suggest you do it gradually as tolerated. Start with a 12-hour fast, and gradually increase it by an hour every three days. In four weeks, you’ll be on the prescribed 16-hour fast. An alternative would be to do it every other day at the start, then gradually increase it to a daily regimen.
Just persevere, unless your doctor tells you to stop. Later on, you’ll realize that the long-term gains will prove to be well worth all the initial challenges.