By Dr. Mercola
Eating more fresh vegetables is one of the simplest choices you can make to improve your health and ward off countless chronic diseases. Virtually any vegetable is good for you… but some are better than others.
To a large extent, the best vegetables for you are those that appeal to your palate and agree with you. I highly recommend listening to your body, in that the foods you eat, including vegetables, should leave you feeling satisfied and energized.
Beyond that, however, if you want to eat the vegetables that have the most nutritional density you should choose from the list of powerhouse fruits and vegetables. These are the foods most strongly associated with reduced chronic disease risk.
41 Powerhouse Vegetables and Fruits Based on Nutrient Density
You may have heard the advice to eat dark green leafy vegetables or focus on including a rainbow of colors (green, purple, red, and orange) when choosing your produce. This is good advice, but a researcher from William Paterson University took it a step further by analyzing levels of 17 nutrients in food considered to be important for lowering your risk of heart disease and cancer.1 These include:
Potassium Fiber Protein Calcium Iron Thiamin Riboflavin Niacin Folate Zinc Vitamin A Vitamin B6 Vitamin B12 Vitamin C Vitamin D Vitamin E Vitamin K
The study calculated how many of the above nutrients (per calorie of energy) were included in 47 fruits and vegetables (based on a 2,000-calorie-a-day diet).
The higher the value, the more nutrient dense the food was determined to be. Forty-one of the foods satisfied "powerhouse" criterion and were more nutrient dense than non-powerhouse fruits and vegetables.
There were some limitations, for instance, the study did not factor in valuable phytochemicals and other so-called xenohormetic compounds (e.g. polyphenols) produced by environmental stressors to the plants that might drastically alter its nutritional merit by optimizing your gene expression and increasing longevity.
That being said, the 41 foods below topped the list based on nutrient density (with some surprising results).2 If you're in a veggie rut, this list offers some great ideas to expand your diet while adding valuable nutrition to your meals.
Item Nutrient Density Score Watercress 100.00 Chinese cabbage 91.99 Chard 89.27 Beet green 87.08 Spinach 86.43 Chicory 73.36 Leaf lettuce 70.73 Parsley 65.59 Romaine lettuce 63.48 Collard green 62.49 Turnip green 62.12 Mustard green 61.39 Endive 60.44 Chive 54.80 Kale 49.07 Dandelion green 46.34 Red pepper 41.26 Arugula 37.65 Broccoli 34.89 Pumpkin 33.82 Brussels sprout 32.23 Scallion 27.35 Kohlrabi 25.92 Cauliflower 25.13 Cabbage 24.51 Carrot 22.60 Tomato 20.37 Lemon 18.72 Iceberg lettuce 18.28 Strawberry 17.59 Radish 16.91 Winter squash (all varieties) 13.89 Orange 12.91 Lime 12.23 Grapefruit (pink and red) 11.64 Rutabaga 11.58 Turnip 11.43 Blackberry 11.39 Leek 10.69 Sweet potato 10.51 Grapefruit (white) 10.47
My Most Recommended Vegetables List
My recommended list of vegetables provides a guide to the most nutritious vegetables, and those to limit due to their high carbohydrate content (think: starch is "hidden sugar"). You'll notice many similarities to the powerhouse vegetable list above. Generally speaking, the greener the vegetable, the more nutritious it will be. I strongly advise you to avoid wilted vegetables of any kind, because when vegetables wilt, they lose much of their nutritional value.
And while I typically recommend choosing organic vegetables as much as possible to avoid pesticides (as well as boost nutrition), wilted organic vegetables may actually be less healthy than fresh conventionally farmed vegetables. Freshness is a key factor in vegetable quality, so if you can't grow your own, look for those farmed locally or, better still, farmed locally and organically. So, as a general guide, the following list of vegetables details some of the best and worst vegetables for your health.
Highly Recommended Vegetables Asparagus Escarole Avocado (actually a fruit) Fennel Beet greens Green and red cabbage Bok choy Kale Broccoli Kohlrabi Brussels sprouts Lettuce: romaine, red leaf, green leaf Cauliflower Mustard greens Celery Onions Chicory Parsley Chinese cabbage Peppers: red, green, yellow and hot Chives Tomatoes Collard greens Turnips Cucumbers Spinach Dandelion greens Zucchini Endive
Use sparingly due to high carbohydrate levels Beets Jicama Carrots Winter squashes Eggplant
Vegetables to Avoid Potatoes Corn
Organic Vegetables May Provide Even More Nutrients
As mentioned, if you can find locally grown organic produce, this is your best bet from a nutritional perspective. It will be fresh (non-wilted), free from chemicals, and more nutritious. According to a study published in the journal PLOS ONE,3 growing tomatoes according to organic standards results in dramatically elevated nutrient content compared to tomatoes grown conventionally, using agricultural chemicals. The organic tomatoes were found to contain 55 percent more vitamin C and 139 percent more total phenolic content at the stage of commercial maturity compared to conventionally grown tomatoes.
You may have noticed that sometimes organic produce, such as tomatoes, are smaller than conventionally grown varieties, but don't let this dissuade you. While many unaware consumers equate size with quality, this simply isn't the case. According to research published in 2009, American produce, while larger than ever before, contains fewer nutrients and tastes worse than it did in your grandparents' days. In fact, the average vegetable found in today's supermarket is anywhere from 5 percent to 40 percent lower in minerals such as magnesium, iron, calcium, and zinc than those harvested just 50 years ago.
As the featured study suggests, jumbo-sized produce contains more "dry matter" than anything else, which dilutes mineral concentrations. Previous research has also shown there can be a nutritional difference between organic and conventionally grown vegetables. For example, a 2003 study in the Journal of Agricultural Food Chemistry found that organic foods are better for fighting cancer.4 A 2010 study conducted by PLOS ONE also found organic strawberries to be more nutrient-rich than non-organic strawberries.5
But perhaps one of the best studies out there on the benefits of organic versus conventionally grown foods is the 2007 Quality Low Input Food Project -- a $25-million study into organic food, and one of the largest of its kind.6 The researchers grew fruit and vegetables, and raised cattle, on adjacent organic and non-organic sites, and discovered that:
- Organic fruit and vegetables contained up to 40 percent more antioxidants
- Organic produce had higher levels of beneficial minerals like iron and zinc
- Milk from organic herds contained up to 90 percent more antioxidants
The results were so impressive they stated that eating organic foods can even help to increase the nutrient intake of people who don't eat the recommended five servings of fruits and vegetables a day. So if you're looking to get more nutritional density out of your food, eating organic is wise choice.
Three More Ways to Boost the Nutrient Power of Your Vegetables
What else can you do to get even more nutrition out of the foods you eat? Plenty, actually. The way in which you prepare and grow your veggies makes a difference, with the following suggestions at the top of my list:
Fermenting is one of the best ways to turn ordinary vegetables into superfoods. The culturing process produces beneficial microbes that are extremely important for human health as they help balance your intestinal flora, thereby boosting overall immunity. Moreover, your gut is the primary locus of your immune system and also literally serves as your second brain, and even produces more of the neurotransmitter serotonin—known to have a beneficial influence on your mood—than your brain does. So, maintaining a healthy gut will benefit your mind as well as your body.
Fermented foods are also some of the best chelators and detox agents available, meaning they can help rid your body of a wide variety of toxins, including heavy metals. When fermenting vegetables, you can either use a starter culture or simply allow the natural enzymes, and good bacteria in and on the vegetables, to do all the work. This is called "wild fermentation." Personally, I prefer a starter culture, as it provides a larger number of different species and the culture can be optimized with species that produce high levels of vitamin K2, which research is finding is likely every bit as important as vitamin D.
For over a year now, we've been making two to three gallons of fermented vegetables every week in our Chicago office for our staff to enjoy. We use a starter culture of the same probiotic strains that we sell as a supplement, which has been researched by our team to produce about 10 times the amount of vitamin K2 as any other starter culture.
When we had the vegetables tested, we found that in a four- to six-ounce serving there were literally 10 trillion beneficial bacteria, or about 100 times the amount of bacteria in a bottle of high-potency probiotics. There are about 100 trillion bacteria in your gut, so a single serving can literally "reseed" 10 percent of the bacterial population of the average person's gut! To me, that's extraordinary and a profoundly powerful reason to consider adding fermented vegetables as a staple in your diet.
Juicing doesn't actually alter the nutritional value of your vegetables, but what it does do is provide an easy way for you to consume more vegetables. Virtually every health authority recommends that we get six to eight servings of vegetables and fruits per day and very few of us actually get that. Juicing is an easy way to virtually guarantee that you will reach your daily target for vegetables. Raw juice can be likened to a "living broth," as it is teeming with micronutrients and good bacteria that many people are lacking.
When you drink fresh-made green juice, it is almost like receiving an intravenous infusion of vitamins, minerals, and enzymes because they go straight into your system without having to be broken down. Drinking your juice first thing in the morning can give you a natural energy boost without resorting to stimulants like coffee. Since the juice is already in an easily digestible form, it can help revitalize your energy levels within as little as 20 minutes.
Plus, juicing helps you absorb all the nutrients from the vegetables. This is important because many people have impaired digestion as a result of making less-than-optimal food choices over many years. This limits your body's ability to absorb all the nutrients from the vegetables. Juicing will help to liberate key nutrients from the tough plant cell walls for you, so you will receive most of the nutrition, rather than having it go down the toilet.
Juicing also allows you to add a wider variety of vegetables in your diet. Many people eat the same vegetable salads or side dishes every day. This violates the principle of regular food rotation and increases your chance of developing an allergy to a certain food. Plus, it limits the number of different phytochemicals in your diet, as each vegetable will offer unique benefits. With juicing, you can juice a wide variety of vegetables that you may not normally enjoy eating whole.
Sprouts are a superfood that many people overlook, as they offer a concentrated source of nutrition that's different from eating the vegetable in mature form. Sprouts in general have the following beneficial attributes:
- Support for cell regeneration
- Powerful sources of antioxidants, minerals, vitamins, and enzymes that protect against free radical damage
- Alkalinizing effect on your body, which is thought to protect against disease, including cancer (as many tumors are acidic)
- Abundantly rich in oxygen, which can also help protect against abnormal cell growth, viruses, and bacteria that cannot survive in an oxygen-rich environment
Some of the most commonly sprouted beans, nuts, seeds and grains include:
Broccoli: known to have powerful anti-cancer properties, courtesy of the enzyme sulforaphane Alfalfa: a significant dietary source of phytoestrogens. Also a good source of vitamins A, B, C, D, E, F, and K Wheatgrass: high in vitamins B, C, E and many minerals Mung bean: good source of protein, fiber, and vitamins C and A Clover: significant source of beneficial isoflavones Lentil sprouts: contain 26 percent protein, and can be eaten without cooking Sunflower: contains minerals, healthy fats, essential fatty acids, fiber, and phytosterols. It's also one of the highest in protein Pea shoots: good source of vitamins A, C, and folic acid, and one of the highest in protein
My two favorites are sunflower and watercress sprouts. They provide some of the highest quality protein you can eat. They are also a perfect complement to fermented vegetables. It is hard to imagine a healthier combination that provides the essentials of nutrition very inexpensively. In addition to their nutritional profile, sprouts are also easy to grow on your own with very little space and time.
Are You Eating Your Veggies?
Despite the fact that vegetables have been proven to help lower your risk of chronic disease and support longevity, most Americans are not eating nearly enough of these natural, relatively inexpensive superfoods. The latest data shows that nearly 23 percent of Americans report consuming vegetables and fruits less than one time daily, with a median vegetable intake of just 1.6 times per day overall.7 This is quite a shame, as people who eat seven or more portions of vegetables and fruit a day have a 42 percent lower risk of dying from any cause, compared to those who eat less than one portion. They also enjoy a 31 percent lower risk of heart disease and a 25 percent lower risk of cancer.8
The research, published in the Journal of Epidemiology & Community Health, is among the first to quantify the health benefits of eating different amounts of fresh produce. As you might suspect, eating any amount of vegetables was better than none at all, but the benefits increased with more servings:
- Those who ate five to seven servings of vegetables and fruits per day had a 36 percent lower risk of dying from any cause
- Three to five servings was associated with a 29 percent lower risk
- One to three servings was associated with a 14 percent lower risk
Most vegetables are not very calorie dense and as a result they probably should constitute the bulk of your diet by volume. Even though my diet is 70 percent fat by calories, if you were to spread out all the food I eat in a day, the largest volume of food would be vegetables. Vegetables contain an array of antioxidants and other disease-fighting compounds that are very difficult to get anywhere else. Plant chemicals called phytochemicals can reduce inflammation and eliminate carcinogens, while others regulate the rate at which your cells reproduce, get rid of old cells, and maintain DNA. Studies have repeatedly shown that people with higher vegetable intake have:
Lower risks of stroke, type 2 diabetes, high blood pressure, Alzheimer's disease, and heart disease Lower risks of certain types of cancer, eye diseases, and digestive problems Reduced risk of kidney stones and bone loss Higher scores on cognitive tests Higher antioxidant levels Lower biomarkers for oxidative stress
Vegetables have an impressive way of offering widespread benefits to your health. When you eat them, you're getting dozens, maybe even hundreds or thousands, of super-nutrients that support optimal, body-wide health. We've compiled an extensive review of the health benefits of vegetables in our Mercola Food Facts Library. If you want to know more, that's an excellent place to start, but suffice to say mama was right: if you want to be healthy and strong, you've got to eat your vegetables.