Dr. David Wells shirtless inside a glacier in Iceland, February 2019.

Since the dawn of time, humans have struggled to get enough to eat, to rest and to stay warm. Naturally, we continue on this path despite most of us being over-fed, sedentary and completely climate controlled. The point of this article is to show the upside of being a little uncomfortable. Don’t worry, I will not advocate in favor of misery. I am only suggesting a little challenge to the way we live and motivate ourselves. To that end, I suggest making friends with being a little bit hungry, a little bit sore and a little bit cold.

A Little Bit Hungry

“The hungry lion runs fastest” anonymous

Intellectually, I know I will not starve to death if I don’t eat all the food on my plate, but part of me thinks I should eat it all just in case I never see food again. The self discipline of leaving some on the plate is hard but I actually feel better if I leave the table just a little bit unsatisfied. “Two bites short,” I call it. The alternative goes something like this; I order a large burrito at a restaurant. When it comes, I see that I really only need to eat half of it to be satisfied. If you think of your stomach as being about the size of your fist, it should be readily apparent that we over-stuff ourselves on a regular basis. If I am smart about it, I cut the burrito in half at that moment. If not, I soon find that I have become engrossed in conversation and eaten two thirds of the burrito before realizing that I am no longer hungry. This is because there is a lag between the time when I swallow my food and my brain gets enough nutrient to know that I have had enough. At that point, I have a third of a burrito remaining on my plate. Being a child of Depression era parents, I can’t waste it and it’s really too small to take home. What to do? Hmm? I guess I’ll just eat it. Does that sound familiar?

I once read an article in a small town newspaper in Oregon about a former cowboy who at the age of 103, rode a horse in the annual town parade. When asked to what he attributed his long and healthy life he said,” I have one rule and one rule only. I always leave the table a little bit hungry.” Damn. Why couldn’t he have said, “I always eat a little bit of chocolate,” or “I get a massage once a week,” or anything pleasant. No. He always leaves the table a little bit hungry. Despite not liking his answer, I gave the matter some thought. After all, the leading causes of death in this country are all related to our diet and lifestyle. Here is what I learned.

Hunger is an exquisitely tuned signaling system to keep our body about the same size as it was a couple of weeks ago. If I starve myself or exercise enough to lose a pound, I will be hungrier until I gain it back. On the other hand, barring interference from emotional signaling, I will stop eating if I am no longer hungry. Observing my kids and grandkids has taught me that kids stop eating when they are no longer hungry. The exception to this if the diet is too high in simple sugars and does not have sufficient nutritional value. Kids (and adults) keep eating to try to get the missing minerals, vitamins, amino acids, fatty acids, etc that they need. Empty calories are just that. They will not satisfy our hunger.

Rule Number One: Eat only high-quality, nutrient-dense foods.

What’s the practical application of this? What has worked for me and many of my patients is to eat just a little bit less than the amount I want. This is because I don’t usually know I have had enough until after I have eaten more than I need. This is one more reason to take time and savor your meal. As I said earlier, “just two bites short” is about the right amount. I tell myself that if I am still hungry in an hour, I can always have an apple or something. Usually, I am not hungry later. The trick is to keep this up for a couple of weeks. After a few weeks, my body adapts to this new normal. This is my new weight. This is my new hunger set point. Obviously, this does not produce dramatic weight loss. If you need a medically supervised fast, this is not for you. On the other hand, if you just want to lose 5 or 10 pounds – and you want it to stay off – this slow, steady physiological change really works.

When I say slow, you can expect to lose about 2 to 4 pounds per month. That may not sound like much but faster weight loss is commonly just water loss anyway. I once lost seven pounds in one day while working in the sun. In a couple of days it was back because I re-hydrated. A lot of “miracle” diets work by causing water and feces to leave. Sure the number on the scale is encouraging, but it is an illusion. Here’s the math for an average person; If you don’t eat for one day, you will lose about a half pound of fat. What about exercise? I will get to that shortly but in terms of weight loss, if you eat until you are satisfied, you will replace what you have burned with exercise. So my “two bites short” recommendation will create a calorie deficit that will enable you to burn one half to one pound of fat per week. Don’t even bother to weigh yourself more than once per week. The variables of water and fecal material make more frequent measurement irrelevant.

There are hundreds of strategies for losing weight from various forms of fasting various restricted diets. Theoretically, they all can work. Do whatever diet you like as long as it contains a variety of nutrient rich, whole foods. What won’t work (unless you are taking dangerous stimulant drugs) is losing weight without feeling hungry. Feeling hungry is the key to success. “Making friends with hungry” is what I call getting over the fear that hunger is a sign of something going wrong. It is a form of mild discomfort similar to feeling sore after exercise. Like breathing in and breathing out, hunger is the counterpoint to satiety.

By the way, you don’t have to be hungry after every meal. Be a little hungry or just reach the point of not hungry but don’t reach the feeling of being full unless you are trying to add muscle mass. For much of my life growing up, I thought that unless I felt full, I hadn’t eaten enough. That is simply not the case. If you are full, you are gaining weight. If you are hungry, you are losing weight. If you are not hungry or full, you are maintaining your weight. It is this simple. And when I say hungry, I am not talking about headache, irritability or other hypoglycemic symptoms. I am talking about an uncomfortable feeling in your stomach. A word of moderation here; if you are continuously hungry for two weeks, your thyroid will down-regulate your metabolism, sabotaging any effort to lose weight. My advice is to not be too strict about my advice. End your meals a little hungry most of the time, not all the time.

This technique works best if you are close to your healthy weight. The reason is because the sensation of satiety depends in part on the production of signaling hormones called “leptins”. These leptins tell your body you have eaten enough. The more fat you have stored, the less sensitive your body becomes to leptins, making you think you are hungry when you have in fact had enough. This is why your body may keep signaling you to eat more food, despite being overweight. BAs you lose weight, you gradually become more sensitive to leptins (making you less hungry) . You can also increase your sensitivity to leptins by cold exposure. Read on.

Rule Number Two: Eat Only Enough To Satisfy Your Hunger If You Want To Remain At Your Current Weight.

Rule Number Three: If You Want To Lose Weight, End Most Meals About Two Bites Short.

A Little Bit Sore

Most people who exercise regularly know that feeling a little sore after a workout is a good thing, so I won’t belabor the point. I do want to underscore the idea that we are talking about a little bit sore. Many people begin an exercise program a little too enthusiastically, leading to being way too sore the next day, which in turn leads to quitting the exercise program. Building muscle requires stressing the muscle with exercise, eating enough and sleeping enough to rebuild the muscle. Any time you start a new program, do about a third of what you think you can do and build on that. Take your time. Growing muscles is not a quick process. When I say do a third of what you think you can do, I am talking mostly about intensity as opposed to duration or repetitions.

You can think of this principle most easily in terms of weight lifting but it applies to any activity. So for example, if you think you can lift 30 pounds 10 times, try lifting 10 pounds 10 times on your first day. Note how you feel the next day. If you are not too sore, then build up the repetitions until you can lift 10 pounds for 3 sets of 10 times each without feeling more than a little bit sore. Now increase the weight and reduce the repetitions. For instance, lift 15 pounds 10 times, rest and repeat twice more. Most serious bodybuilders do around 10 to 15 repetitions, 3 to 4 times (sets) on any given muscle. Those repetitions are usually paired with alternatively working an opposite motion for the same number of reps and sets (as in biceps and triceps or chest and back). Eventually (or if you are already in very good condition), you can lift very few times at closer to your maximum resistance. You might for instance do 3 sets of 3 to 5 reps. The point is to have a very hard time completing the last set.

Most weight lifting programs are described in terms of sets and reps. You may wonder why they don’t prescribe how much weight to lift. This is because the amount of weight varies from person to person and is based how many reps and sets you can do before the muscle is unable to do another repetition. This is called muscle failure. Strength training is one endeavor where your goal is to reach failure. You can reach failure by doing a single rep or a hundred. Strength and muscle gains are achieved either way though if you are training for a specific activity, it’s best to do that activity. Training is specific because a lot of it happens in your nervous system. In a study where the subjects trained only one bicep muscle, researchers found that while the trained side increased in strength by 35%, the untrained side increased by 20%. This proves how much of strength training is actually neural facilitation.ⁱ

Try to avoid the temptation to lift more to boost your ego or social standing. That often results in injury and at the very least, results in poor form and consequent poor results. One of the best ways to gain muscle and strength is to lift light to moderate weights very slowly. Think Tai Chi speed. Perfect form, very slowly with a light to moderate weight will give the best results and also greatly reduce the risk of injury. For more on this, see my article on Super Slow, High Intensity Training.

If you really overdo it, you may get what is called Delayed Onset Muscle Soreness or DOMS. This is a condition in which proteins have leaked out of the muscle and cause a delayed inflammatory response. DOMS is characterized by appearing two days after the exercise (as opposed to the next day) and getting progressively worse over the next few days, taking about a week to subside. This is not a case of “if a little bit is good, more must be better.” DOMS is muscle damage that does not lead to muscle growth.

If you do it right, you will feel just a little thick and sore in the muscles you worked yesterday. People who do resistance training call that feeling “pumped” because the muscle feels bigger. It actually is a little bigger because the muscle slightly inflames during the healing process. Don’t work that same area until the feeling subsides. Work another body region or function. There are a multitude of programs to rotate through the major muscle groups on a weekly basis. After you have been doing one program for a month, change it up a little. As a body builder once told me, “The best program is the one you’re not doing.”

Rule Number Four: Do Resistance Training Sufficient to Feel Just A Little Bit Sore The Following Day.

If I’m not a little sore when I wake up in the morning, I figure I’m not trying hard enough. Or as one of my patients said, “If I wake up in the morning and absolutely nothing hurts, I’m dead.” Make friends with being a little bit sore.

If you are trying to build muscle mass, you will also have to eat more, particularly more protein. The minimum recommended amount of protein per day to maintain your weight is .8 grams of protein per kilogram of body weight. You will want to double that amount to gain muscle. You also need to consume more calories. This means eating a few bites more than you need to satisfy your hunger. Again, it’s not a good idea to stuff yourself at any one meal, so you may have to eat every few hours to get enough. If you find yourself producing intestinal gas, you are eating more than you can digest. If that gas smells like rotten eggs, you are eating more protein than you can digest. In addition to protein, you need to consume enough calories to support your desired muscle mass. To be sure that you are building muscle rather than fat, measure your waistline. You will want to gain weight without increasing your waistline.

Of course it is also important to do aerobic exercise. The same principle applies. Start with walking thirty minutes. If you want to take it another step (see what I did there), add a little intensity by going uphill for part of the walk. Of course, you can also walk farther and or faster. To challenge your heart, add intervals of race-walking or sprinting, mixed with walking. Go hiking up hills. You get the idea.

If you are moving at a comfortable pace, you will be mostly burning fat for energy. That means that you can go a long time without refueling. In fact, you can run a Marathon distance on about a half pound of fat. If you have been running or going uphill, you may feel muscle soreness related to breaking down and building muscle, but feeling sore after a long walk is most likely due to dehydration, rather than the effects of exertion. Nonetheless, for 24 hours after aerobic exercise, you will be burning energy at a higher rate. You will sleep better, digest better, feel better. It’s not exactly feeling sore, but there is a “spent but energized” feeling that comes after aerobic exercise.

Just A Little Bit Cold

Our bodies respond to cold by increasing our metabolism, and increased metabolism is what we want. Increased metabolism means more energy and faster fat burning. It also means less risk of killer diseases. So why do we avoid cold? For most of human history, we had to work very hard to get enough calories to sustain life. We know that being cold costs calories, so we avoid it, despite the limitless availability of restaurants and grocery stores. We try very hard to conserve energy.

How cold are we talking about? Just a little bit. If you are shivering, you are too cold. What we want to trigger is literally called, “non-shivering thermogenesis.” When we shiver, we burn glucose for energy. When we are cold but not shivering, we burn fat. Better yet, we train our bodies to keep burning fat preferentially, as if we were doing aerobic exercise. To explain this, I have to explain how different fat cells work.

We usually think of fat cells as passive storage depots but actually, they are metabolically active. They come in two basic types, white and brown. The white ones are primarily storage depots but they do make hormone-like molecules that send signals to increase hunger, blood pressure, risk of heart disease, etc. White fat is primarily stored in the trunk around the viscera. Too much white fat is not good. Brown fat cells on the other hand are brown because they are full of energy-producing, fat-burning mitochondria. You want more brown fat cells. Here is where it gets interesting. Exposure to cold stimulates brown fat cells to burn fat faster. That’s right. Your body starts burning fat at a faster rate to raise your temperature in response to cold. Better yet, exposure to cold causes white fat cells to become “beige” fat cells! These beige fat cells have more mitochondria and burn fat more efficiently. It all makes sense if you think about it. To stay warm in a cold environment, you need to burn more fat and make more energy.

So how do we use cold to our advantage? Be just “a little bit” cold. Not enough to shiver but enough to feel uncomfortable. The winter I first learned about this, we set our thermostat at 63 degrees Fahrenheit. I continued to wear short sleeve shirts despite feeling uncomfortably cool. I did wear thick socks. If I had been sitting still for awhile and was getting cold, I would get up and move around to warm myself. After a couple of months, my basal temperature went from it’s usual 97.6 (low end of normal) to a the ideal 98.6. My energy level increased and my TSH (a measure of thyroid function) went from slightly high (indicating a sluggish thyroid) to the ideal range. Some other symptoms and signs improved as well. In short, being cold kick-started my metabolism. During the summer months, swimming is a good way to get some cold exposure. I take cool showers all year. In the winter, I mix in some warm water with the cold. The rest of the year, my shower is at whatever temperature comes out of the cold tap. I actually shower outdoors most days but that’s another story.

How much fat is burned? That depends a lot on the individual and how much exposure to cold. One study of lean, young men who exercised for 45 minutes in 68 degree water found that they ate 41% more food compared to when they exercised in 91 degree water. This suggests but does not prove that they burned 41% more calories. If you think of how hungry you get after swimming in cold water, this makes sense. If you are trying to lose weight, the hard part would be not eating as much as you want to after the swim.

I can’t give you an exact number of calories burned per time in a particular temperature range but I know I lost eight pounds in a week when I was out photographing in Yellowstone in January. Despite being dressed for cold, I was cold all week (at one point the temperature got down to 27 degrees below zero). I didn’t have the option of just eating more food, so I lost weight.

If a little cold is good, is a lot better? In a word, “No”. As I mentioned above, cold to the point of shivering does not increase brown fat conversion or produce other changes leading to increased metabolism. You may have read about people like Wim Hof who swim in ice water or meditate naked in the snow, claiming to have found the fountain of youth. I don’t think extreme cold is an unqualified good. Many of the effects of exposure to extreme cold result from increased production of cortisol, an anti-inflammatory hormone. Suppressing inflammation in general is a good thing but cortisol also suppresses immune response so you don’t produce symptoms of illness even if the illness is continuing to spread. It does not make you free of infection and there is a rebound effect. Your adrenal glands can only produce cortisol for so long. Stress also causes in increase in cortisol but no one advocates more stress. If you feel an exhilarating rush from a cold shower or dip in the ocean, you are feeling the release of noradrenaline, another stress hormone that produces a kind of high. While this is a good thing if you have enough energy, adrenaline is also a stress on the body and should be avoided if you are feeling weak or are recovering from an illness. Adrenaline consumes a lot of glucose. If you feel tired later in the day after exposure to cold, you may want to dial it down. Cold, like exercise or hunger is a stressor. We want to challenge our bodies but not to an extreme.

I prefer just being in a slightly uncomfortable cool environment. When I feel like I need to shiver, I breathe deeply and try to relax more, bringing blood to all parts of my body. I am trying to get my body to produce heat without stressing or shivering. This is my way of calibrating my response.

Despite my cautious statement above, mild cold exposure can improve immune response. This is mediated in part by noradrenaline. A study of lean young men who sat in a cold bath for an hour found increases in their immune response, including an increase in natural killer cells.ⁱⁱ The immune enhancement was even better if they exercised prior to cold exposure. Personally, I hike or bike early in the morning when it is still cold outside. I under-dress for the occasion (shirtless while hiking), using exercise instead of clothing to warm myself.

If exposure to cold enhances immune response, why do we “catch cold” more frequently when in cold environments? This may be due to drying of mucus membranes in the upper respiratory tract, losing the protective benefits of a mucus coat, along with a withdrawal of blood (and therefore immune cells) from mucus membranes due to cold. I wear a buff or other facial covering when exercising in cold air. I do the same or put a little lubricant in my nostrils when flying because airplane cabin air is extremely dry.

One of the great things about cold exposure is that it can help your body repair telomeres. Those are the ends of your DNA that fray and degrade a little every time cells divide. The slow degradation of telomeres is how we age. Eventually, cells can’t divide properly and cells die. If enough critical cells die, so do we. Hunger, particularly fasting, also stimulates telomeres to repair.

Rule Number Five: Allow Yourself To Be Just A Little Bit Cold At Least Part Of The Time.

Conclusion

I am advocating living a richer sensory experience. As implied by the old saying “Hunger makes the best sauce”, we enjoy our food more when we are hungry. Feeling fully spent after exercise is a lovely mix of peaceful and vibrant. Diving into cool water feels exhilarating. Feeling the sun warm your skin afterwards is also delightful.

There is an emotional spinoff as well. We have greater confidence when we are not worried about being hungry, cold or facing the challenge of exercise. When I travel overseas on photography trips, people who know I am particular about what I eat ask, “What if you can’t find anything there to eat?” My reply is, “I’ll be hungry.” I know I will be uncomfortable but I won’t die. I have made friends with hunger. I do not fear it. There is a lot of freedom in that.

This embrace of life’s challenges and discomforts may even translate into more willingness to take social or emotional risks. Speaking up for what you want, even when it is uncomfortable may lead to actually getting what you want. At the very least, you will feel better about standing up for yourself. Telling truth to power isn’t comfortable, but that’s how the world gets better. As Chicago Tribune columnist Mary Schmich said, “Do one thing every day that scares you.”ⁱⁱⁱ What I am saying is that courage to face some discomforts in life may lead to courage in other areas as well.