Try This: Simple Math Equation To Optimize Your Metabolic Health

Do you want to know a crazy statistic?

Even though there’s more education on healthy eating than ever before, studies have found that the US population is consuming more than 300% of the daily recommended amount of added sugar (1).

Even a lot of my health-conscious friends are completely surprised to find out that they are struggling with high average blood sugar or an elevated Hemoglobin A1c. Some are shocked to find themselves firmly in the pre-diabetic range even though they are younger and pretty active.

So the question is, how the hell could this be happening?

Well, Big Food loves using buzzwords like “low-fat,” “keto,” “vegan,” or “gluten-free” to trick us into thinking their foods are healthy. Plus, they use ingredients that we don’t recognize as “bad,” but still have a high blood sugar impact—pretty messed up, right?

I’m not saying the motivations are always intentional, but a lot of food marketing and food lobbying is banking on consumers not being aware of how specific ingredients impact our health.

What if we became truly aware of those red flags that put our metabolic health in danger?

What if we start taking control and become the CEO of our own health?

When we know what to look out for, we can better navigate the food system to take the power away from Big Food and put it back into our own hands.

But where do we start?

One of the lowest-hanging fruits and biggest returns on your health is knowing what foods spike your blood sugar, because blood sugar imbalances happen to be a primary driver of insulin resistance and poor metabolic health.

If you struggle with your sleep, creeping weight gain, poor immunity (especially in kids), mood swings, high cholesterol, or even migraines, my protocol this week is for you.

It’s inspired by a super-easy math equation that anyone can do (including kids!) to understand how any particular food (especially those that come in a bag or a box) is going to impact your blood glucose.

That way, we can have the autonomy to decide how a food is going to make us feel, instead of leaving it up to “Big Food” to do it for us.

It’s not about eating “perfectly” or achieving some ideal state of health, it’s about tapping into awareness to make conscious decisions.

So…. what’s the simple math equation that can radically improve our health? It’s calculating net carbs!

Now before I break down how to do it, let’s first unpack the good, bad and ugly around carbohydrates.

Why Are We So Carb-Crazy?

Carbohydrates are basically a bunch of sugar molecules strung together that our bodies break down and use for energy.

I know carbs have gotten a bad rep since keto and low-carb diets hit the mainstream, but burning carbohydrates for energy isn’t necessarily a bad thing.

In fact, our bodies are designed to use glucose (when it’s available) as an energy source. It’s so precious to the body that we store it in our muscles and liver. We even have a mechanism that converts protein into glucose (called gluconeogenesis) when our blood sugar runs too low.

Carbs really only become a challenge when we overeat the wrong kind. You don’t have to be a nutritionist to know that “bad” (I don’t love that word, but you get the point) carbs come from cookies, cakes, pretzels, crackers—basically anything made from simple sugars. Processed and packaged foods are the biggest culprits.

We call these “refined carbs” because the fiber is removed during manufacturing, leaving behind the starchy part of the grain that turns to straight-up sugar in the body.

To make matters worse, the refined carbs in ultra-processed foods are usually combined with poor-quality fats to make them more palatable. Plus, they contain significant levels of BPA and phthalates, which interfere with blood sugar control and contribute to weight gain (2)(3).

The “good” carbs are your complex carbs from whole foods (fruits, vegetables, nuts, seeds, and whole grains). These contain fiber which slows sugar absorption, and doesn’t spike your blood sugar as high as simple carbohydrates.

Note: Certain complex carbohydrates like sweet potatoes, beets, and oats can spike your blood sugar, BUT they contain fiber, vitamins, and minerals, making them more beneficial than problematic for most people to enjoy. I still enjoy them AND I’m just mindful about my consumption of them.

All in all, it’s refined carbs that put our metabolic health in danger, when (and this is key) we overdue them.

Why Are Refined Carbs Such A Problem?

Tens of thousands of scientific studies have proven a link between high intake of refined carbs in the diet, blood sugar imbalances, metabolic dysfunction, insulin resistance, weight gain, and chronic diseases like obesity, type 2 diabetes, heart disease, cancer, IBS, and Alzheimer’s (410).

In addition to that, sleep, immunity, focus, and attention are also affected by high sugar intake, especially in children (1114).

Unfortunately, refined carbs (and sugar) are everywhere and make their way into just about every processed food. Yes, even a lot of “healthy” processed and packaged foods out there on the shelves at Whole Foods and Trader Joe’s contain refined carbs in one way or another.

When I’m searching for healthy snacks, the first things I look for on the label are refined carbs, total sugar, and vegetable seed oils, but misleading marketing can make them hard to identify in a hurry.

That’s why I quickly calculate the net carbs for any food with a label to figure out if it’s going to spike my blood sugar.

This simple, easy math equation increases awareness of the potential blood sugar impact a food will have, so you can decide whether it’s worth purchasing (it might be!). I feel a lot better knowing and making that decision for myself rather than trusting food companies to do it for me.

How Calculating Net Carbs Can Be Helpful

Net carbs are the total number of carbohydrates in a food that enter your bloodstream, turn to sugar, and trigger insulin release. If you haven’t heard of net carbs, don’t worry, most people haven’t. (I’ll admit, I didn’t really know about the term until a few years ago.)

Looking at the nutrition facts and calculating net carbs can help you cut through clever marketing tactics that are a load of crap. You can quickly identify how a packaged food could impact your blood sugar and metabolic health when consumed over time.

And it only takes a matter of seconds! Ready to learn how to do it?

The Protocol

I. How to Calculate Net Carbs. Michael Pollan said it best, “If it came from a plant, eat it; if it was made in a plant, don’t.” Since it’s not always possible (or practical) to avoid foods made in manufacturing plants, I would rephrase this last part to say, “If it was made in a plant, be weary—and calculate net carbs.

Calculating net carbs is super easy to do off the top of your head. Just subtract total fiber from total carbohydrates and BOOM! That’s it! You generally now know the blood sugar impact of the food (some examples below).

There’s no golden rule or reference value for knowing when net carbs are going to be a problem for your metabolic health. But you can follow some general guidelines to make it easier to identify foods that are most likely going to spike your blood sugar, all in a matter of seconds.

Important: I’m not worried about the net carbs naturally present in whole food. I’m talking about the foods that come in a bag, box, or tube made in a manufacturing plant.

And, I’m not saying to never ever eat these foods. Eating foods high in net carbohydrates is okay to do now and then. When they become a staple in the diet—that’s when they are problematic for our health. This is especially important for young children, who are targeted the most by high sugar foods.

Try This:

1. (Total Carbohydrates) – (Dietary Fiber) = Total Net Carbs. There’s no definitive “good” or “bad” number to know when net carbs are going to be a problem. The goal is to identify foods that are very high in carbohydrates and very low in fiber. If the difference between total carbohydrates and fiber is high, that will ultimately tell you that the net carbs present in the food are going to be a problem for your blood glucose.

A good rule of thumb is: for every 5 grams of total carbohydrates, to have 1 gram of fiber, or a 1 to 5 ratio (15).

Harvard Medical School recommends a 10:1 ratio because it’s supposed to represent the blood sugar impact of an actual whole grain (16)(17). But whole grains don’t necessarily mean no blood sugar spike (something my CGM taught me). That’s why I like to shoot for the 5:1 rule (15).

A note about allulose and sugar alcohols…If present in a food, they will be listed under “Sugar Alcohols” on the label.

  • Allulose (a rare sugar found in wheat, corn, and certain fruits) and erythritol (a type of sugar alcohol) can’t be broken down or metabolized by the body, which means they don’t turn to sugar.These two sugar alcohols are treated like fiber and subtracted from total carbohydrates. (Here’s an excellent articleby Dr. Peter Attia that dives deeper into the topic of allulose if you’re interested in learning more.)
  • Other types of sugar alcohols like xylitol, maltitol, sorbitol (hint: if it ends in “ol” it’s probably a sugar alcohol) are divided by two and then subtracted from total carbohydrates along with fiber (see below) because they still have a little blood sugar impact.

One last thing before we get into some sample calculations—sugar alcohols are okay in moderation but try to avoid making them a staple in the diet. They can irritate the gut lining and cause gastrointestinal problems when consumed in high amounts (18).

Personally, I had to start cutting out sugar alcohols from my diet this year because I noticed that my skin (which is deeply connected to our gut health) would be extremely dry and sensitive anytime I ate them. And I was having them almost every morning in a no-sugar mushroom coffee mix I bought. I’m not saying that’s going to happen to everyone, but gut irritation is a known challenge surrounding sugar alcohols.

Note for those in the UK: Counting net carbs is easier than in the US because the total carbohydrates on the label already subtracts dietary fiber (so it’s already calculated for you!)

II. Net Carb Sample Calculations. I have some examples below on how to calculate net carbs. I provided three examples: one for total net carbs for a packaged food I would consider “okay” to eat in moderation, “good” (because it has a ratio of 5:1 or less), and one that contains sugar alcohols.

Try This:

Example 1. Moderation: Siete Sea Salt Chips

Siete Chips are an awesome alternative to potato, wheat, or corn chips. Hats off to the company for designing a product that’s grain-free, gluten-free, and tastes delicious. I’m a big fan.

Even though they have 0g of added sugar, they are made from cassava flour, which still significantly spikes my blood sugar. Stick to enjoying these on occasion and try to keep to the serving size.

Total Carbohydrates: 19g
Dietary Fiber: 2g
Ratio: approximately 10:1

Net Carbohydrates: 17g (19g total carbs – 2g dietary fiber)

Example 2. Good: Paleonola Vanilla Bean

I wanted to include Paleonola because I consider it a better alternative to conventional granola brands. It’s grain-free and made from nuts instead of oats, but it still has a few grams of added sugar.

However, in this case, net carbohydrates are still low (which means it won’t have a major blood sugar spike) because the total carbohydrates are relatively low and the fiber is high.

This is a perfect example of a food that contains added sugar but is still low in carbs and contains other good stuff (healthy fats and fiber) in levels high enough to curb any blood sugar spike.

Total Carbohydrates: 6g
Total Fiber: 2g
Ratio: approximately 3:1

Net Carbohydrates: 4g (6g total carbs – 2g dietary fiber)

Example 3. Sugar Alcohol Sample Calculation

Total Carbohydrates: 32g
Total Fiber: 2g

Example #1: Allulose or Erythritol: 10g
Calculation: (32g total carbs – 2g dietary fiber – 10g allulose)
Total Net Carbs for Allulose or Erythritol: 20g net carbs

Example #2: Sugar Alcohols (Other): 10g
Calculation: (32g total carbs – 2g dietary fiber – 5g sugar alcohol [10g sorbitol divided by 2])
Total Net carbs for Sugar Alcohols: 25g net carbs

III. Watch out for hidden sources of refined carbohydrates and sugar. Certain certifications like “vegan” and “gluten-free” have standards that need to be met. But unfortunately, we have no standards (or warning signs) on foods that negatively impact our metabolic health and make us sick.

That’s why we need to look out for packaged foods that contain refined flour, which turns into sugar and acts just like sugar in our bodies.

The biggest culprits? Large amounts of gluten and grain-free flours like cassava or tapioca passed off as healthy alternatives to wheat flour and corn, or brown rice syrup used as a sweetener.

It’s best to minimize packaged foods containing these flours or sugars (especially if they are in the first few ingredients, which means they are used in higher amounts). These are going to wind up having the same blood sugar impact as plain old sugar.

Again, it’s important to be super clear that you can still enjoy these foods. Just don’t make them the staple of your diet. It’s not about being perfect, it’s about making smart conscious choices. Awarness over perfection – all day.

Here are a few of the main grains to focus on minimizing:

Try This:

1. Watch out for these common sources of refined carbs. The following ingredients drive up the number of total net carbs in packaged foods. Wheat flour (even the “whole grain” kind) found in bread, crackers, chips, and desserts are the common culprits. The ones you have to watch out for are the “grain-free” or “gluten-free” alternatives to wheat listed below.

  • Cassava flour
  • Tapioca flour or tapioca starch
  • Rice Flour
  • Potato flour or potato starch
  • Corn flour or corn starch

What happens if we eat these foods all the dang time? We’re more likely to increase our risk of insulin resistance, inflammation, weight gain, and chronic diseases like type 2 diabetes, obesity, infertility, Alzheimer’s, and so much more.

2. Watch out for these common sources of sugar. In addition to the gluten-free grains listed above, I want to quickly cover the many hidden names of sugar.

Some sources of sugar are obvious because they say “sugar” in the title, but others are downright sneaky. Here are some less obvious sources of sugar on ingredient labels. I can’t list all of them (there are hundreds), but here are a few I see most frequently:

  • Sucrose, beet sugar, blackstrap molasses, brown sugar, cane juice crystals, caramel, carob syrup, date sugar, fruit juice, maple syrup, molasses, malt syrup, corn syrup, dextrose, maltodextrin, R-ribose, galactose.

Final Thoughts

Refined carbs and sugar are a major problem in the global food system. Almost every food in a bag or box has them, and they are the biggest contributors to insulin resistance and inflammation—the biggest drivers of chronic disease, which accounts for 90% of the 3.8 trillion dollars spent on healthcare every year.

The poet and farmer Wendell Berry once said, “People are fed by the food industry, which pays no attention to health, and are treated by the health industry, which pays no attention to food.”

Big Food is often out for one thing (and it’s not our health, that’s for damn sure). We have the power to change that.

If we continue to eat these foods, Big Food will continue to make them. 

So it’s up to us. If we are educated and aware we can consciously make smart food choices that are going to keep us metabolically healthy. The food industry will follow in our footsteps and shift the market to meet our demands.

Calculating net carbs (in addition to reading the ingredients label and spotting refined flours and sugars) is an awesome way to start doing this.

If you’re calculating net carbs, I would love to hear your experience with it. Is it easy? Challenging? Have you tried calculating net carbs with your kids?

Feel free to reply back to this email and let me know how it’s going, or connect with the community on the Dhru Purohit Podcast Facebook page.

Here’s to your metabolic health,
Dhru Purohit

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