Dr. John Day, Cardiologist

Podcast: Play in new window | Download

Subscribe: RSS

The 6 Best Vegetables and Fruits for Weight Loss

In my work with thousands of patients in preventing heart disease, I have observed that people with the healthiest weights tend to eat the most vegetables and fruits.  In this article, I discuss the latest medical research on the best vegetables and fruits for weight loss.  I also cover which vegetables and fruits to minimize if you are trying to get down to a healthy weight.

How do vegetables and fruits cause weight loss?

For those of you who want to know how vegetables and fruits cause weight loss, here are the five best scientific explanations from medical studies.

1. Low glycemic load.

Most vegetables and many fruits have a low glycemic load.  This means that these foods are converted to sugar by the body very slowly.  Thus, the overall sugar impact from these foods is incredibly low.   An additional benefit of foods with a low glycemic load is that they tend to keep hunger away.

In contrast, foods with a high glycemic load, like most desserts, breads, pasta, cereals, and other processed foods are rapidly converted to sugar by the body.  In fact, even whole wheat bread and most breakfast cereals are converted to sugar by the body even faster than a Snickers bar.

The glucose surge from most breads, pasta, cereals, and other processed foods are then followed by an insulin spike.  In no time at all, you’ll find yourself hungry again.

2. Fiber is filling.

Along with protein, fiber is very filling.  Fiber slows down the digestion process and allows people to feel full longer.

3. High in micronutrients.

Many overweight people suffer from a micronutrient deficiency.  Hunger may really just be the body’s way of signaling to you that it needs a particular micronutrient.  This could explain why I have observed in my patients that as they eat more vegetables and fruit their hunger seems to lessen.

4. Fiber increases metabolism.

One great way to increase your caloric burn, even while you are sleeping, is to eat foods high in fiber like vegetables and fruit.  Fiber requires more energy to move through the digestive system than readily processed foods like most snack foods, breads, or cereals.

5. Healthy gut microbiome.

As I have discussed in a recent blog article, having the right gut microbes in place can effortlessly allow you to maintain a healthy weight.  If you feed these healthy gut microbes the food they need, like fiber, they will reward you with a healthier weight.

Best Vegetables and Fruits for Weight Loss Study

To study the effects of different vegetables and fruits on weight loss, researchers from Harvard and Tufts University recently analyzed food intake and weights over a 24-year period of time from 133,468 people.  With the reams of data collected, researchers gained many key insights from this study.  Below are the six best vegetables and fruits they found for weight loss.

Please note that the expected weight loss from these foods are based on eating one serving daily for an entire year.  Thus, if you ate one vegetable or fruit from each of the six items listed, for an entire year, you could expect to lose an average of 1.9 pounds each year.  While this may not seem like much, over 20 years it could amount to a 37 pound weight loss.

1. Edamame/tofu/soy: 0.62 pound weight loss per year

As most readers know, edamame/tofu/soy is not technically a vegetable but rather a legume.  However, as this study lumped them in with vegetables, I included it here.

The soy bean was clearly the very best food for weight loss in this study.  Perhaps this helps to explains why there is so much less obesity in Japan, China, and Korea.

In some circles, edamame/tofu/soy has a bad reputation in the U.S.  This is likely because most Americans don’t eat real soy beans but rather the highly processed GMO soy isolates.

In Asia, where people eat the natural whole soy bean, the scientific data are pretty clear.  Soy beans appear to be protective against heart disease and cancer, even breast cancer.

We regularly eat the organic whole bean forms of edamame/tofu/soy in our home. We enjoy them dry roasted and lightly salted like nuts.  We also like edamame spaghetti for pasta dishes, tofu in a stir-fry, or even unsweetened soy milk for breakfast.  I also like fermented soy beans in the form of natto.

If you are wondering where to find dry roasted edamame beans, edamame spaghetti, or natto, try your local health food store, Asian store, or online through Amazon.

2. Cauliflower: 0.34 pound weight loss per year

Cauliflower is a cruciferous vegetable.  However, I have separated out cauliflower from its peers due to the especially potent weight loss effects it packs.  In our home, we love cauliflower raw or as part of a stir-fry dish.  It also works great in mashed potatoes or as a substitute for creamy sauces.

3. Apples/Pears: 0.31 pound weight loss per year

I was definitely surprised to see apples and pears so high on this list.  However, when you look at the scientific data, the pectins and other phytonutrients in apples and pears have unique effects that not only help with weight loss but also in the prevention of diabetes and cardiovascular disease as well.

4. Berries: 0.28 pound weight loss per year

I’m sure berries on this list came as no surprise to any readers.  Berries not only have a relatively low glycemic load but they are also off the charts in antioxidants.

5. Cruciferous vegetables: 0.17 pound weight loss per year

Ah, the cruciferous vegetables.  My favorite.  Overall, this group of  vegetables, which includes cauliflower, broccoli, kale, brussels sprouts, bok choy, and cabbage fared quite well when it comes to weight loss.  In addition to their weight loss effects, this special group of vegetables is also very effective in preventing cancer as I discussed in blog #6.

6. Green leafy vegetables: 0.13 pound weight loss per year

I was a bit surprised to see the green leafy vegetables down so far on the weight loss list.  Perhaps this is because of the company it keeps.  In other words, most people eat these vegetables with salad dressing which may undo many of the potential health and weight loss benefits of green leafy vegetables.

Are your wondering where your favorite vegetable or fruit falls on the weight loss list?  In general, this study found that the higher the fiber content and the lower the glycemic load, the better the vegetable or fruit performed for weight loss.

Vegetables Causing Weight Gain

Not all vegetables cause weight loss.  Indeed, the starchy vegetables in this study did not cause weight loss but rather weight gain.  From this study, here are the top three vegetables and legumes causing weight gain in order.

Please note that corn and peas are not officially “vegetables” However, as the authors of thus study have lumped them in with other vegetables, I have done the same as well.

1. Corn

2. Peas

3. Potatoes

Unfortunately, the vegetables causing weight gain are also the main vegetables eaten by most Americans.  Thus, if your goal is weight loss, then minimize corn, peas, and potatoes.

Fruit Causing Weight Gain

As with vegetables, not all fruits cause weight loss.  In general, most fruits, other than melons or fruit juice, cause weight loss.  Once again, if your goal is weight loss, then minimize melons and fruit juice.

Take Home Message of this Study

In the big picture, vegetables and fruits are incredibly nutritious and prevent weight gain, heart disease, and cancer.  While there is a lot of confusion about nutrition in health books and on the internet, the one area where most people can agree is on the need for more vegetables and fruits.

In my opinion, the one saving grace of the new U.S. dietary guidelines is the call for nine servings of vegetables and fruits each day.  If you are a mindful eater who does not like to “count” your food, then just remember to always fill your plate with mostly vegetables and fruits and you will be just fine.

What vegetables and fruits help you the most in minimizing hunger and maintaining a healthy weight?  Please leave your comments below.  Also, if you have any questions about this article, or the study discussed, please leave your questions below and I will try my best to answer every question.