Eating for Glucose

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Endless Energy (get the book or audiobook) by Peter Hollins is a guide to becoming insanely energetic.

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Episode Transcript

Eating for energy consists mainly of focusing on blood sugar levels. You can think of the amount of readily available glucose in your bloodstream as a physiological analogue to “energy”—it’s the literal fuel you need to power everything in your body, including the thoughts in your brain. However, there are consequences for having both too much and too little: you know the consequences for too little glucose, but with too much, the body will overcompensate and create a “crash” effect in your energy levels. Keep your blood sugar levels constant and moderate, and the machine of your body will be well-functioning.

The easiest way to start thinking about blood sugar levels is to talk about the glycemic index (GI). The GI is a measure of how quickly your body breaks down different foods, mostly carbohydrates, into glucose. In other words, it measures how much and how quickly a food will affect your blood sugar levels. The higher the GI, the more quickly it evaporates into your bloodstream as glucose.

After a typical meal, your blood sugar level spikes and then insulin is released to regulate it. Your body has ways to keep your blood sugar in a relatively stable range—i.e. releasing stored energy from muscle, liver or fat tissue when blood sugar is low, or releasing insulin to usher excess away when blood sugar is high. When the body detects a large amount of blood sugar, a proportionately large amount of insulin is released, and this is what creates the aforementioned crash effect on energy levels.

Thus, the goal with eating for glucose and abiding by the glycemic index is to try to keep your blood sugar levels as constant as possible. Avoid energy peaks and crashes, and instead cultivate sustained, moderate energy throughout the day. You can do this by understanding timing and food selection.

The lower the GI of a food, the less extreme its effect on the insulin response and the more slowly and steadily it releases sugars into the blood. The result is stable energy levels and appetite. Foods with a higher GI cause the body to release huge spikes of insulin that then clear blood sugar more quickly, leaving you with a “crash” afterwards—one that feels exhausting and can make you hungry all over again. Basically, lower GI foods lead to more stable blood sugar, energy levels, appetite, and mood, while higher GIs can cause us to feel extreme blood sugar and energy fluctuations, plus incite cravings that force us to eat more when we don’t need to.

The blood-sugar roller coaster is all about highs and crashes from eating refined carbohydrates and simple sugars. Though GI is not the only feature to look for in a food, it’s an important thing to consider with regards to energy. GI says nothing about the caloric value or the nutrient density of a food, so it’s worth remembering to use GI as only one factor of many when planning a diet for optimal energy.

Glycemic load (GL) is another measure, and essentially takes into account the quantity of carbohydrates you’re eating at any time, and the effect this has on your blood sugar. Portion size makes a difference. The higher the glycemic load, the higher the spike in blood sugar levels. Ideally, you want both the GI and GL to be as low as possible. Luckily, the foods with the lowest levels are conveniently the ones that are healthiest in other ways too—i.e., they’re packed with vitamins, minerals, fiber, and antioxidants.

There’s nothing wrong or unhealthy about carbohydrates per se, but the more refined varieties (i.e. the ones that are immediately converted into glucose) are more likely to lead to unstable blood sugar and the resulting energy spikes and slumps. Fruits and vegetables, after all, are carbohydrates too, but if a food also contains lots of fiber and water, its total glycemic load may be low enough to offset the fact that the bulk of its calories come from simple sugars. So, although things like bananas and potatoes are high-GI foods, they are natural, plant-based foods that still contain plenty of nutrition to outweigh any negative GI effects.

When planning a diet to optimize your energy levels, opt for small amounts of high-quality fats, plenty of protein, and carbohydrates primarily from plant sources. Avoid nutrient-poor refined carbs like cakes and white bread, sugary sweets, soda, white rice, and pasta. If you do decide to have them, try smaller portions and combine them with other low-GI foods so that the total meal’s GI is still on the low side. And of course, if you must eat high GI foods, eating them with fat and protein will aid in slowing the glucose absorption.

First, take a look at your diet as it currently is, and figure out the foods you could replace. It can start in a small way. Have wholegrain bread instead of white, bran flakes instead of sugary cereals in the morning, brown rice and other whole grains instead of white, and of course every fruit and vegetable, particularly those that have the highest fiber and water content. There’s no need to strictly count carbohydrate grams or be too restrictive about your food choices. Instead, simply get into the habit of choosing the fuel for your body that will “burn the longest” and keep your metabolic fire ticking slowly and steadily, rather than cycling quickly between deathly tired and completely wired up.

Start the day with oatmeal and fruit, some wholegrain toast and peanut butter, or an omelette with veggies. Bran flakes or a smoothie with protein powder are also a great idea. For lunch, try a whole-meal bread sandwich with cheese, smoked salmon, chicken, or a veggie option like hummus. Serve this with a salad, or try a fiber-rich soup or some brown rice with veggies, tofu, or a boiled egg. For dinner, have more of the same or try any meal that’s evenly balanced between carbohydrates, fat, and protein—i.e., a protein source like meat or legumes, a carbohydrate source like potato, brown rice, corn or other whole grain, and a fat source like cheese, avocado, nuts or olive oil. Instead of high-GI bombs like ice cream or cake for dessert, try stewed fruit, herbal tea or a few blocks of 75 percent dark chocolate.

Overall, remember that GI isn’t the be all and end all of a food; some healthier options will actually have a GI rating higher than the “unhealthier” version, so always use your discretion. Remember, too, that overall GL matters, and that it’s OK to have even super-refined carbohydrates on occasion if they’re paired with a mostly healthy diet and enjoyed only in small quantities. In the real world, there are many overlapping factors that determine the effect a food will have on blood sugar; GI is simply a guide. However, if you make a point to avoid eating obviously nutrient-poor refined carbs and balance the rest of your meals, you should reap the benefits. You obviously possess enough Internet savvy to purchase this book, so you can easily research “low-GI foods” and build your own meals and substitutions.

One final thing to bear in mind is the timing of your meals. A steady, even blood sugar level is maintained if you eat moderately sized meals spaced evenly throughout the day. Though there’s some evidence for the health benefits of fasting, the truth is that long periods with low blood sugar, or forcing the body into a ketogenic state (when you are burning your body fat stores for energy, essentially), may be hell on mood and energy levels, even if it does help you shed a few quick pounds. Predictably, when you finally break your fast, insulin will also come rushing out, and a similar energy spike and crash will frequently occur. Opt instead for regularly spaced meals, and avoid letting yourself get famished—this will only mean you have less willpower at the next meal to turn down unhealthy foods.

Though you should watch the kind of carbohydrates you eat, there’s no point in avoiding them altogether. If you demonize carbs and eliminate them entirely, you may find yourself feeling absolutely starving and grouchy, for no good reason. Carbs are necessary for basic brain function and to power every aspect of your metabolism. Think of carbs as the kindling of your metabolic fire, protein as the structural component to help you repair and maintain your muscles, and fat as essential for energy, but also the proper functioning of your endocrine system and several other important mechanisms in the body.

You don’t need to give up drinking fruit juice or never have a donut again, but aim to eat well at least 80 percent of the time, and you’ll iron out the bumps on that blood-sugar roller coaster. Vegetables, whole grains, nuts, meat, dairy and eggs will keep you stable and help you get on with the business of life.
Shoring Up Deficiencies

Finally, there’s one last way that your diet can help you achieve a more consistently high and stable energy throughout the day: supplements.

A healthy diet is the first step, and indispensable. But there’s also a lot you can do to give your body a boost on top of that. We’ve seen that energy imbalances can come from sleep or ignoring your circadian rhythms, from psychological problems—i.e., stress and trauma—and from physical or mental overexertion—i.e., pushing yourself beyond your natural limits until your body forces you to stop by burning out. But exhaustion, as we’ve seen, is also about nutrition, and not just on the macro level. Hidden vitamin and nutrient deficiencies, or even hormonal disturbances can sneakily work to undermine energy levels in the background, even though we’re doing our best to sleep well and de-stress.

This is where supplements come in. You might have tried to implement some of the changes mentioned above (that is, getting better sleep, eating low-GI foods) and still find that your focus is weak, your habits are poor, and you generally feel a lack of resilience and enthusiasm for life. Simply not being tired is not quite the same as being energized and wired up for life. If you’ve tried to relight that fire, and still you feel as though you’re merely plodding along, you may need a little something extra.

Supplements play two roles: they can be corrective and address some specific deficiency you have (for example, vitamin D capsules that correct an insufficiency and tackle the cause of your fatigue) or they can be additive, meaning you take them without having any deficiencies, but because you want to enhance your performance, energy or resilience. The latter are called nootropics, and could spell the difference between merely chugging along and getting stuck, and actually making your dreams come true.

You could ask your doctor for a blood test if you have persistent fatigue, to help you identify any specific deficiencies. You could also opt for a DIY home test kit that’s available in some areas. Common deficiencies leading to fatigue include magnesium, vitamin B-12 (and this is not just for vegans or vegetarians!), iodine, melatonin, vitamin D (especially if you live in a country that gets very dark over the winter) coenzyme Q10, and iron (more common in women).

If your fatigue is persistent, you may be surprised at how much energy can be gained from merely making sure your body is getting the micronutrients it needs. Don’t make any assumptions—even those of us who “eat well” can get vitamin and mineral deficiencies, so don’t rule this possibility out. As for nootropics, there’s a whole world of supplements out there designed to boost performance and well-being—some supported by science, some only with anecdotal evidence. Red panax ginseng, pine pollen, Rhodiola rosea and other “adaptogens” like ashwagandha, turmeric, tulsi (holy basil) and licorice root have all been hailed as great stress-relievers, energy boosters, and general well-being tonics. These are all supplements that have a range of anecdotal and scientific backing—but everyone’s body composition is different, so it’s best if you perform your own due diligence.
A Note on Water

Was there ever any debate over this? Being dehydrated significantly reduces your energy levels, mental performance, and overall brain health. Our brains are 70 percent water, so it stands to reason they are affected the most when you are in a state of dehydration.

A UK study found that ninety minutes of sweating without additional hydration shrinks the brain as much as a year of aging or almost three months of Alzheimer’s Disease (Kempton, 2011). Temporarily, one might hope. Another study suggested that driving while dehydrated can be similar to driving drunk because of the decrease in focus and reaction time, as well as impaired motor skills (Loughborough University, 2012). And there is very little margin for error, as well. Significant detriments to analytical thought, short-term memory, long-term memory recall, problem-solving, and general cognitive performance were found in just a one percent level of dehydration (Riebl, 2013).

Thus, drink more water throughout the day for more energy, and make sure both your body and brain are well-oiled and lubricated. Don’t rely on feeling thirsty to understand that you need more water. Preempt this, because the thirst response does not activate until you are already dehydrated, and it will be too late by that point. Take a proactive approach to drinking more water and account for weather, environmental conditions, or other factors that would necessitate greater intake. The old maxim of “eight glasses of water a day” may not necessarily be accurate or even necessary, but you probably need more water than you are currently getting.

Drink more water than you think you should and you’re on the right track to keeping your body fueled.

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