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Slow Carbs, Not Low Carbs: The Truth about Low-Carb Diets

Slow Carbs, Not Low Carbs: The Truth about Low-Carb Diets

The low-carb frenzy hit its zenith in the early 2000’s and has since ebbed and flowed in popularity. I’ve seen patients get impressive results doing very low-carb diets, but eventually many become burned out and regain the weight as the novelty of eating bacon and other formerly forbidden foods becomes monotonous.

Traditional thinking suggests carbohydrates are bad for you. I have something surprising to say that might go against everything you’ve heard: Carbs are the single most important thing you can eat for health and weight loss. In fact, I often say my plan is a high-carb diet.

But wait, you say, don’t carbs contribute to insulin resistance, heart disease, and other health concerns?

Some do, but the truth is more complicated. You see, “carbohydrates” encompasses a huge category. A hot fudge sundae and cauliflower both fall into the “carbs” category, yet they are entirely different foods.

In fact, almost all plant foods fall into the carbs category. These are what I refer to as slow carbs, which are low-glycemic and don’t spike your blood sugar or insulin. These slow carbs come loaded with nutrients, fiber, and amazing molecules called phytochemicals.

When you eat a cornucopia of fresh fruits and vegetables teeming with phytonutrients — carotenoids, flavonoids, and polyphenols – they help improve nearly all health problems, including dementia, diabesity, and aging.

Ideally, about 75% of your carb intake should come from non-starchy veggies plus low-glycemic fruits. By volume, most of your plate should be carbs. Note I said volume, not calories. Many plant-based carbs actually have very few calories.

Why All Carbs Are Not Created Equally

Carbs are necessary for long-term health and brain function. But not the doughnuts, breads, bagels, and sweets we typically think of as carbs. These are highly processed foods, stripped of their nutrients and fiber. When I say carbs, I mean real, whole plant foods containing all the vitamins, minerals, fiber, and phytonutrients that create health.

Unfortunately, most people are not eating these plant foods. They are eating quickly absorbed carbs from sugar, high fructose corn syrup, and white flour, which are very efficiently turned into belly fat in the body.  After you eat a high-carb meal, your insulin spikes and your blood sugar plummets — leaving you very hungry. That is why you crave more carbs and sugar, and eat more.

The important difference is in how carbs affect your blood sugar. Calorie for calorie, sugar is different from other calories that come from protein, fat, or non-starchy carbs such as greens. Sugar scrambles all your normal appetite controls, so you consume more and more, driving your metabolism to convert it into lethal belly fat.

To drive home the point that not all calories – or carbs – are created equally, refer to my past blog in which I illustrate  that, while both soda and broccoli fall into the carbs category, 750 calories of soda and 750 calories of broccoli behave entirely differently once they enter your body.

Here’s a quick refresher.  Your gut quickly absorbs the fiber-free sugars in the soda. The glucose spikes your blood sugar, starting a domino effect of high insulin and a cascade of hormonal responses that kicks bad biochemistry into gear. The high insulin increases storage of belly fat, increases inflammation, raises triglycerides and lowers HDL, raises blood pressure, lowers testosterone in men, and contributes to infertility in women.

High-fiber, low-sugar carbs, such as broccoli, are slowly digested and don’t lead to blood sugar and insulin spikes. These slow carbs reduce cancer risk and increase your body’s ability to detoxify.

Therein lies the key difference. Slow carbs like broccoli heal rather than harm.

Choosing the Right Carbs

You may not realize this, but there are no essential carbs. There are essential fats (omega-3s) and essential proteins (amino acids), but if you never had any carbs again, you would survive.

That being said, good-quality carbs that come from plant foods provide unique benefits, including high levels of vitamins and minerals, fiber, and special plant compounds with healing properties called phytonutrients or phytochemicals. Phytochemicals are medicinal molecules such as curcumin in turmeric, glucosinolates in broccoli, anthocyanidins in berries and black rice, and so on.

Many of these foods are high in fiber, which helps buffer out their sugar content. That is one reason why eating a cup of blueberries has a dramatically different impact than put-ting four teaspoons of sugar in your coffee. Both have about 16 grams of sugar, but the nutrients, phytonutrients, and fiber in blueberries help buffer out that load, whereas the sugar-filled coffee simply raises your insulin levels and plummets your blood sugar, leaving you running for a muffin or other quick sugar fixes.

Besides stabilizing blood sugar by slowing the absorption of carbs, fiber feeds the friendly flora in your gut and scrubs your intestines, thus supporting a healthy digestive tract. Try to gradually increase your fiber intake to 30 to 50 grams a day. That becomes easy when you focus on viscous fiber from legumes, nuts, seeds, whole grains, vegetables, and low-glycemic-load fruits.

When you focus on these low-glycemic-load plant foods, your weight normalizes. You feel better without the sugar crashes. You reduce your risk for numerous diseases.

To simplify things and help you make optimal choices when it comes to carbs, I have divided them into four categories – green, yellow, red, and forbidden.

Green Carbs: Eat Freely

Slow-burning, low-glycemic vegetables should be the basis of your diet. Fill your plate with broccoli, asparagus, spinach, chard, kale, cabbage, bok choy, and more. These are truly an unlimited food!

Seaweed is another smart choice. Some weeds are good for you, and the weeds of the sea are among my favorite. If you’ve never tried them, be adventurous. Kombu, nori, hijiki, and wakame are all extraordinarily high in minerals, protein, and healing compounds.

Yellow Carbs: Eat in Moderation

  1. Whole grains. Brown, black, and red rice; quinoa; amaranth; buckwheat; and teff are delicious gluten-free grains. Black rice has as many anthocyanidins as blueberries and a low-glycemic load. Called forbidden rice, it was once eaten only by Chinese emperors.
  1. Fiber-rich, phytonutrient-rich legumes are underutilized in our culture. They slow the release of sugars into the bloodstream and help prevent the excess insulin release that leads to insulin resistance. Try red, French or regular lentils; chickpeas; green and yellow split peas; soybeans (edamame is a great snack); pinto, adzuki, black, navy, and other beans.
  1. Dark berries. Blueberries, cherries, blackberries, and raspberries are filled with phytonutrients. The richer the color, the more “medicine” you get. Eat as much as one-half cup a day. Organic frozen berries can be used in your protein shakes.
  1. Enjoy up to two pieces of the following fruits each day:

Stone fruit. Plums, peaches, nectarines, and their variants are known as “stone fruit.” They are healthy and full of fiber and healing chemicals.

Red Carbs: Eat Limited Amounts

You should limit your intake of the following:

  1. Starchy, high-glycemic cooked vegetables. These include winter squashes, peas, potatoes, corn, and root vegetables such as beets. Starchy vegetables raise blood sugar more quickly, so they should be consumed in smaller quantities (up to one-half cup a day) and ideally in the context of other foods that reduce the overall glycemic load of the meal.
  1. High-sugar fruits. Melons, grapes, and pineapple contain more sugar than the fruits listed above, so they should be limited to a half-cup treat once a week, and avoided altogether if you are on a low/no sugar protocol.

Forbidden Carbs: Avoid Processed Carbs Completely.

  1. Gluten-containing whole grains. Stay away from wheat, barley, rye, oats, spelt, kamut, and triticale.
  1. Processed foods (including “low carb” foods). Avoid highly processed, factory-manufactured Frankenfoods. Many of these processed foods will have health claims such as “low carb,” “no sugar added,” or “high fiber.” Always stick with real, whole, unprocessed foods. Remember, if it has a health claim on the label, it is probably bad for you.
  1. Dried fruit. They have a high-glycemic load.

Can a Low-Carb Diet Benefit You?

While I think nearly everyone does well incorporating nutrient-dense slow carbs, there are many cases in which a very low-carb diet can be beneficial. For people with type 2 diabetes, high blood sugar, and/ or obesity, you may need to restrict or cut out even starchy veggies and fruit for a period of time before re-introducing them back into your diet.

The trick involves gradually introducing slow carbs. As insulin sensitivity improves, you can increase your consumption of slow carbs like lentils, yams, fruit, and whole grains from time to time.

Once you’ve balanced your insulin levels and dealt with any deeper issues, you can move on to a slow-carb diet (about 30 grams per meal and 15 grams per snack).

No matter what, you want to keep your glycemic load low. Always avoid refined sugars, refined carbs, and processed foods. If you do decide to eat grains, keep them to a mini-mum. Any grains can increase your blood sugar. Consider sticking with quinoa or black rice.  And minimize starchy, high-glycemic cooked vegetables, such as potatoes, corn, and root vegetables, such as rutabagas, parsnips, and turnips.

Another trick is to always eat a carb with some protein, fiber, or anti-inflammatory fat to help buffer the carbs sugar load.

Please refer to my book The Blood Sugar Solution 10-Day Detox Diet for a comprehensive list of smart carbohydrates. I’ve divided the plan into three phases, with step-by-step directions on what to eat and when, as well as a road map for what to do after your 10-Day Detox and how to transition to a long-term health and weight-loss strategy – all based on my original book on balancing blood sugars – The Blood Sugar Solution.

If you’ve ever done a low-carb diet, did you attain the success you desired? Did you eventually reintroduce slow carbs back into your diet? Share your story below or on my Facebook page.

Wishing you health and happiness,
Mark Hyman, MD

Mark Hyman MD is the Medical Director at Cleveland Clinic’s Center for Functional Medicine, the Founder of The UltraWellness Center, and a ten-time #1 New York Times Bestselling author.