Nutrition Basics- Part 3: Carbohydrates and the Glycemic Index

Nutrition
Written by Larry Betz

Steady Energy or a Hard Crash: The Carbs You Choose Decide Which One You Get

By Larry Betz | Prepared Not Paranoid https://www.preparednotparanoid.com/


You know the feeling. It's 2:30 in the afternoon. Your energy falls off a cliff, your focus is gone, you're hungry again even though you just ate, and your patience is running thin.

Most of the time, that crash goes back to what you ate a couple of hours earlier.

Few foods cause more confusion than carbohydrates. One diet says cut them all. Another says build every meal around them. Here's the truth: carbs aren't the enemy. The wrong carbs, at the wrong time, without a plan, are.

On a normal day, that crash shows up as an afternoon slump and cravings. In an emergency, it matters even more, because you need steady energy and a clear head for hours at a time. This post shows you how to tell the difference between carbs that sustain you and carbs that set you up to crash, and which ones belong in your emergency pantry.

Understanding Carbohydrates

Carbohydrates are organic compounds composed of sugars, starches, and fiber. Plants produce carbohydrates through photosynthesis, storing them in the form of saccharides (sugars).

In the human body, carbohydrates serve primarily as a source of energy. When not used immediately, they are stored as glycogen in the liver and muscles. Once those stores are full, and you're eating more calories than you burn, the extra energy ends up stored as body fat.

While the body can generate glucose from non-carbohydrate sources via a process called gluconeogenesis, carbohydrates from whole plant foods remain essential because they also provide fiber, vital nutrients, and health-promoting phytochemicals.

The Three Types of Carbohydrates

  • Sugars: simple carbohydrates, like the sugar in fruit, milk, honey, table sugar, and syrups

  • Starches: long chains of glucose, in potatoes, rice, oats, bread, beans, and corn

  • Fiber: carbohydrate your body can't fully digest, in vegetables, fruit, beans, whole grains, nuts, and seeds

Fiber doesn't raise your blood sugar the way sugar and starch do. It slows digestion, feeds your gut, and keeps you full. Most Americans get only about half the fiber they need. Part 7 of this series covers it in detail.

The Glycemic Index (GI)

Understanding the glycemic index (GI) is essential when evaluating the types of carbohydrates you eat. The GI is a scale from 0 to 100 that measures how quickly a carbohydrate-containing food raises your blood sugar levels after eating, compared with pure glucose at 100.

Foods with a high GI (70 and above) such as white bread, instant rice, or sugary breakfast cereals, cause rapid spikes in blood sugar. In contrast, low-GI foods (55 or less), like steel-cut oats, lentils, chickpeas, and most legumes, are digested and absorbed more slowly, resulting in a gradual rise in blood glucose. Medium-GI foods (56 to 69) fall in between, including options like rolled oats, sweet potatoes, and white rice.

This is important for managing energy levels, appetite, and long-term metabolic health. Choosing lower-GI carbohydrates can help improve insulin sensitivity and lower the risk of chronic conditions like type 2 diabetes and heart disease.

Here's where common foods land.

A few surprises worth knowing:

  • "Whole wheat" bread is often no better than white bread. The flour is ground so fine it digests fast. Breads made with 100 percent whole grain, or with visible grains and seeds, do better.

  • How you cook matters. Pasta cooked al dente has a GI around 38. Cook it 20 minutes and it climbs to about 61.

  • Instant means faster. Instant oatmeal and instant potatoes are higher than their less processed versions.

  • Most whole fruit is low GI, thanks to its fiber and water.

Glycemic Load: The Fuller Picture

While some experts now emphasize the glycemic load (which factors in portion size) for a more complete picture, the GI is still widely used as a helpful reference when selecting carbohydrate-rich foods.

Here's why it matters. Watermelon has a high GI (72), but a serving is mostly water with only a little carbohydrate, so its glycemic load is just 4. That's low. A big bowl of cornflakes, on the other hand, is high on both.

The easy way to lower the spike: You don't have to memorize numbers. Pair your carbs with protein, healthy fat, and fiber, and the whole meal digests more slowly. Research has also found that eating your vegetables and protein first, and your starch last, leads to a smaller blood sugar rise than eating the same foods in the reverse order.

Simplifying Carbohydrates: What You Need to Know

Carbohydrates come in many forms, but what matters most for everyday health and preparedness is how they affect your blood sugar, energy levels, and digestion throughout the day.

Simple Sugars

Simple sugars are found in foods like ripe fruits, fruit juices, table sugar, and sweetened snacks. Added sugars and sweets, especially in liquid form, are digested and absorbed rapidly, and they cause quick spikes in blood sugar, followed by sharp crashes. This can leave you feeling tired, hungry, or irritable shortly after eating.

Whole fruit is a different story. Its fiber and water slow things down, and most whole fruits land in the low GI range. Natural sources like whole fruit are fine in moderation, especially when paired with protein or fat, but it's best to limit added sugars and sweetened products for sustained energy and metabolic health.

What's new (checked October 2026): The Dietary Guidelines for Americans, 2025 to 2030, released January 7, 2026, take a much harder line on added sugars and on highly processed foods made from refined starches and sugars. The natural sugar in whole fruit and plain milk doesn't count as added sugar. Part 10 of this series covers sugar and high fructose corn syrup.

Complex Carbohydrates

Complex carbohydrates are found in whole grains like oats, quinoa, and brown rice, as well as legumes and fiber-rich vegetables. These tend to fall on the low to medium end of the GI scale, depending on how processed they are, and beans and lentils are among the lowest of all. Because they break down more slowly, they help maintain steady blood sugar levels and provide more sustained energy throughout the day. Including these in your meals can help reduce cravings, support metabolic health, and keep you feeling full and focused for longer periods.

Refined Carbohydrates

Refined carbohydrates include white bread, white rice, crackers, pastries, and many packaged snack foods. These are technically complex carbohydrates, but they've been highly processed, stripping them of fiber and nutrients. As a result, they digest quickly and rank in the upper-medium to high range on the GI scale. Eating refined carbs leads to rapid spikes in blood sugar, followed by a crash in energy, which can result in fatigue, mood swings, and increased hunger shortly afterward. For better energy and health, it's best to limit refined carbs and instead choose whole, minimally processed alternatives.

Here are a few easy swaps.

Resistant Starches

Resistant starches are a unique type of carbohydrate that act more like fiber. Found in foods like cooked-and-cooled potatoes and rice, green bananas, lentils, and legumes, they are not fully digested in the small intestine. Instead, they pass into the colon, where they are fermented by gut bacteria. Resistant starches promote a slow, steady release of energy. They also support gut health and may improve insulin sensitivity. Including resistant starches in your diet can help you feel full longer, support digestive health, and provide more stable energy throughout the day.

Make leftovers work for you. Cooking potatoes, rice, or pasta and then chilling them overnight raises their resistant starch. Yesterday's potato salad, cold rice bowl, or pasta salad is an easy win. Chill cooked rice within an hour or two and keep it cold.

Carbohydrates for Everyday Health and Preparedness

For those focused not only on preparedness but also on overall everyday health, choosing the right carbohydrates means having foods on hand that offer nutrient density, stable energy, and digestive support.

Whole grains are a smart staple; they store well, especially when kept in airtight containers or vacuum-sealed in a cool, dry environment. One thing to know: brown rice and whole wheat flour contain natural oils that can go rancid within months at room temperature. Keep them cool or in the freezer and rotate them often. White rice and rolled oats keep much longer, which is why many families store some of each.

Sweet potatoes, beans, and lentils are also excellent options, as they can be stored dry or canned and provide long-lasting, slow-burning fuel for both daily nutrition and emergency situations.

Here's what belongs on your emergency shelf.

When Quick Carbs Are the Right Call

There are times when fast sugar is exactly what you need:

  • During long, hard physical work, like clearing debris or hauling water, quick energy from fruit, dried fruit, or a sports drink keeps you going.

  • For someone with diabetes having a low blood sugar, fast-acting sugar is the treatment.

Diabetes and low blood sugar: If anyone in your family has diabetes, especially if they take insulin or other medication that lowers blood sugar, keep fast-acting sugar in your emergency kit and go-bag: glucose tablets, juice boxes, or regular (not diet) soda. The American Diabetes Association's "15-15 rule" is 15 grams of fast-acting carbohydrate, recheck blood sugar in 15 minutes, and repeat if it's still low. If someone becomes confused, can't swallow safely, or passes out, call 911. Talk with your doctor about an emergency plan, including whether glucagon belongs in your kit.

Ask Yourself

  • Do my family's carbs come mostly from whole foods, or mostly from packages?

  • When do I crash during the day, and what did I eat a couple of hours before?

  • Would the carbs in my emergency pantry give us steady energy, or just quick spikes?

Remember

Steady blood sugar means steady energy and a clear head. Choose carbs that come with fiber, pair them with protein and healthy fat, and save the quick sugar for when you truly need it.

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Go Deeper

The Prepared Not Paranoid Family Nutrition Guide. This post shows you which carbs to choose. The guide shows you how to build them into real meals: a plate-building plan and sample day for the whole family, a full shelf-life chart for your pantry staples, 15 shelf-stable pantry recipes, a special diets chapter for diabetes and other medical needs in an emergency, and a 30-day calculator for your family's food supply. [Get it here: LINK]

Tools I recommend: The airtight food storage containers and kitchen tools I recommend are in my Amazon store. https://amzn.to/4yM747h

Related reading:

References

Disclaimer

This article is for general informational and educational purposes only. It is not medical advice and is not a substitute for guidance from your physician or a registered dietitian. If you have diabetes or prediabetes, take medication that affects blood sugar, or are pregnant, talk to your doctor before changing your diet. Affiliate disclosure: I've linked to products from my Amazon store that I personally recommend. As an Amazon Associate, I earn from qualifying purchases, at no extra cost to you. Thank you for supporting my work.

If someone with diabetes becomes confused, can't swallow safely, or passes out, call 911.


Awareness gives you time. Time gives you options.


The prepared protector is someone who's decided that loving someone means being ready for them, not just hoping things go fine.

Prepared Not Paranoid. Protecting the Most Vulnerable Among Us.

Larry Betz https://www.sedonastrengthandmobility.com
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