Carbs: Good or bad?
By: Jodi Leslie Matsuo, DrPH, MPH, RDN, LDN
Here it is! Our first Kukui Lifestyle Medicine Clinic (aka KLMC) blog!
My husband and I started KLMC with the need to help people. The purpose of this blog goes along those lines. Helping keep people informed. Cutting through the jungle of misinformation. Learning health information that is built on real evidence. After all, knowledge is power. The power to change your health, the health of your family, and to live a long life.
I was thinking about some common questions that come up from patients. One of the main misconceptions I hear almost every week is that “carbs is bad”. Or that “carbs are fattening”. That is so far from the truth. Before I explain further, let me explain exactly what a “carb” is.
Carbohydrates (“carbs”) are one of 3 main types of nutrients in the body. It is the body’s main and most important source of fuel. Fuel that your heart, brain, lungs, and other organs need to function, to work. Carbs, in itself, is not bad, but indeed very important for our health.
There are 2 types of carbs – complex and simple. Examples of complex carbs are brown rice, poi, sweet potatoes, bread fruit, 100% whole wheat bread or noodles, oatmeal, edamame, and other beans. Whole fruits and vegetables also are considered complex carbs.
Simple carbs include white rice, bread, or noodles, as well as fruit drinks and juices, soda, sugar, honey, maple syrup, and agave. Candy, cookies, cakes, doughnuts, pizza, and french fries are also in this same category.
You’re probably seeing the pattern here.
Complex carbs tend to be more “whole” foods. Meaning, many of them are eaten in the natural form it was grown. They all contain fiber and naturally contain vitamins, minerals, and phytochemicals (plant chemicals) that all fight disease.
On the other hand, simple carbs = highly processed foods. Foods stripped of fiber, vitamins, minerals, and phytochemicals. Foods commonly eaten with other not-so-healthy foods. Not only that, simple carbs tend to be used as vehicles for butter, fat, oil, cheese, and sugar.
Here’s some food associations to make this point clear.
In Hawai‘i, when you think of white rice, what association do you make with that? Spam musubi. Plate lunch (not the healthy one). Kalua pig & cabbage and rice.
What do you think when you hear “white bread”? Hamburger and fries. Hot dog. Ham sandwich.
Others are more obvious..pizza! Pizza that’s glopped with cheese and meat. On white crust (you probably didn’t visualize whole-wheat crust). Basically, a vehicle for oil and fat.
The question then…is it the carbs that is fattening? Or the type of carbs? Or what people tend to eat with the carbs? Or the hitchhikers on the carbs – oil, cheese, fat, sugar?
The other thing that feeds into the “carbs are fattening” idea is the amount of carbs people are used to eating. Think plate lunch again. At least half the plate is simple carbs – two big scoops of white rice plus one scoop of macaroni salad
When ordering fast food, about 2/3 of your meal is simple carbs – white hamburger bun, French fries, and soda.
What about spaghetti dinner? White noodles and garlic bread.
So it’s not only the type of carbs, but the amount of carbs in proportion to the rest of your meal. And the greater part of your meal that is carbs, translates to less of your meal from vegetable or fruits.
And don’t forget the carb vehicles, that adds calories and fat:
Mac salad = Vehicle for mayo
French fries = Vehicle for oil
Spaghetti noodles = Vehicle for meat and cheese
Garlic bread = Vehicle for butter
This reminds me of a person I know, whose doctor told them to stop eating carbs, as his advice to weight loss. That was 10 years ago. This person, to this day, doesn’t like to eat carbs, believing it is fattening. And the result…she is still overweight!
Can people overeat on complex carbs? Yes, but this only happens for those who eat more processed whole grains. For example, whole wheat bread or noodles. I’ve never seen or heard anyone, or personally experienced, overeating on unprocessed carbs – for example, poi, edamame, fruits, or vegetables.
Keep in mind that health is more than your weight on the scale. It’s about what’s going on inside of you. Unclogging your arteries. Fighting cancerous cells. Reducing inflammation. Making your cells more sensitive to your body’s insulin so you can reduce your diabetes medications.
A 2018 study of >15,400 people, followed for 25 years, found that both a low carb diet (a diet where <40% of calories were from carbs) and a high carb diets (>70% of calories from carbs) were associated with an increased risk of dying and a shorter life span.
Researchers compared the quality of the diets among the low carb eaters. The low carb dieters that ate an animal-based diet (beef, pork, lamb, chicken, cheese), ate lower amounts of fruits and vegetables and higher amounts of animal-based protein and saturated fat. They also had increased risk of dying, compared to those following a low carb, plant-based diet (vegetables, whole grains, and nuts).
What about the high carb eaters? Those following a high carb diet tended to eat more refined (simple) carbs, which may reflect poor diet quality overall. While high carb eaters also had an increased risk of dying, the difference in life expectancy (expected years of life) between them and those with the lowest risk of dying (those who ate 50-55% of calories from carbs), were only 1.1 years.
To put it more simply, following a diet that includes 50-55% of your calories from carb had the lowest risk of dying. However, if you choose to increase the amount of carbs you eat to >70% of your calories, you only risk losing a year of life. Ideally, you want your carbs to be complex carbs.
Based on this study, researchers concluded that animal-based, low carb diets (such as Paleo and keto diets) should be discouraged. This study adds to growing evidence on the importance of following a whole food, plant-based diet.
Bottom line: Carbs is needed for healthy body functions. Choose complex carbs, preferably those unprocessed or whole. Limit simple carbs or avoid them altogether. And as I always recommend, go plant-based.
Reference: Sidelmann, S.B., Claggett, B., Cheng, S., Henglin, M., Shah, A., Steffen, L.M., . . . Solomon, S.D. (2018). Dietary carbohydrate intake and mortality: a prospective cohort study and meta-analysis. Lancet Public Health, 3: e419–28.