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Vegetables reflect the changing of the seasons; the different colors that that they show indicate the phytonutrients that are in the foods. A good guideline is to always try and eat any perishable food from local sources and in the season of its growth. Be particular about organic quality. The challenge is to consider these things but to make sure to get variety. This is particularly true if you live in an area where local weather, poor soil, or lack of local variety are a problem. There are hundreds of varieties of vegetables. Listed below are the general characteristics of some popular vegetable varieties.

Cruciferous Vegetables

The cruciferous vegetables are very important for most people living in the northern hemisphere in a four seasons climate. They include cabbage, broccoli, cauliflower, and curly kale. Vegetables in this particular family are best when they are cooked. They can sometimes be difficult to digest if they are not cooked well. Cabbage has been a staple food in Europe for centuries, both cooked and fermented as sauerkraut.

These vegetables are very nutrient-dense, and they are often known to have particular healing modalities, including anti-inflammatory properties. A review of 206 human studies and 22 animal studies in the Journal of the Academy of Nutrition and Dietetics showed a pronounced protective effect of several varieties of vegetables, including cruciferous vegetables, carrots, and allium vegetables.

Cruciferous vegetables include arugula, bok choy, broccoli, broccoli rabe, brussels sprout, cabbage, cauliflower, Chinese cabbage, collard greens, daikon, kale, kohlrabi, radish, rutabaga, and turnips. Foods that hold their nutritional value for a long period of time and don’t wilt or dissipate quickly are foods that are very important when the weather is cooler (or in cold weather). These foods have more warming qualities.

Squash & Pumpkin

Squash is a very diverse family of vegetables that originate in the northern hemisphere in the Americas; the cultivation of food crops in both North and South America rotated around maize (corn), beans, and squash. They were sometimes referred to as the three sisters. The combination of these three foods gave people an incredibly rich and nutritionally diverse diet that sustained the native peoples of North America for centuries before the arrival of the Europeans.

They are a fantastic autumn and winter food. They can be stored for months without losing their nutritional value. They are a great source of complex carbohydrates and are very sweet to the taste, so they are very useful in cooking. Their sweetness makes them popular as vegetable dishes (cooked with beans) or even used as desserts. Because of their natural sweetness and more complex sugars, they are often used by us for clients with type 2 diabetes when switching to a Human Ecology Diet.

The summer squash—which are sometimes referred to as cucumbers in shape and consistency—are foods that don’t have that particular density of nutrition, but they are cooling and best used in season with the exception of being useful to preserve as pickles. The squash family include pumpkins, acorn squash, Hokkaido pumpkins, butternut squash, cheese pumpkins, Hubbard squash, kabocha squash, and turban squash.

Roots & Tubers

Roots and tubers are vegetables that grow below the ground. Most of the roots and tubers have been used traditionally as good sources of complex carbohydrate all over the world. They have often been used as a primary food source when climate or other environmental conditions were not favorable to growing grain.

Some tubers have an even broader range of nutrients than grains. This is probably why—before grain cultivation and in semitropical climates—they were the principal foods. They even have vitamins A and C. Roots are the energy storage system of the plant. Similar to some of the other foods that we have talked about, these foods are nutritionally dense and have traditionally been considered as essentials to a healthy diet. Foods like carrots and onions, potatoes, yams, and sweet potatoes will last a long time without losing their nutritional qualities.

These vegetables include (some were listed earlier as cruciferous as well) carrots, daikon, parsley root, parsnips, beets, celeriac, radish, rutabagas, turnips, burdock, salsify, and taro. (Botanically, onion, garlic, shallots, spring onions, and leeks are alliums.) The most popular tuberous roots are sweet potatoes, yams, and potatoes.

Greens Glorious Greens

Hearty greens are a basic requirement for healthy eating. Some cruciferous vegetables mentioned earlier will also fit into this category. If you are eating a plant-based diet, I think it is very important to have green vegetables every day. The unique concentration of nutrients in dark-green vegetables lie in the rich mix of vitamins and minerals. These greens pack a more significant punch than the salad greens we will talk about next. If you have a good seasonal balance, you are going to have a good nutritional balance. The dark-green vegetables include, but are not limited to, collards, mustard greens, turnip greens, chard, spinach, and kale. Most of these vegetables are best lightly cooked (more so with kale).

Lighter Greens (Salad Vegetables) Even when the climate is cold, people (especially those who have eaten a lot of animal fats) need some raw food. Raw foods are helpful in cleaning out the gut and dissolving fatty tissue. Have small amounts of raw food daily—but remember it’s easy to eat too much of it in a cooler climate.


Whether it’s pressed salads or light fresh salads, consume these cooling foods in the summertime. Varieties of lettuce, “rocket,” or any of the spring greens—these leafy greens can be eaten raw and are good to have on a daily basis. These salad vegetables are relaxing by nature. Aside from their cooling qualities, they are an excellent source of vitamins and enzymes. We manufacture enzymes in our bodies, but it’s good to get some enzymes in our diet (although many are destroyed during digestion). Eating salad vegetables or raw vegetables ensures that you get the full spectrum of the foods you need. Vegetables reflect the seasons, so let the seasons be your guide. Food is often shipped long distances, so use produce that has traveled only when local or regional supplies are inadequate. Vegetables that are seldom cooked include arugula, endive, chicory, dandelion greens, escarole, radicchio, watercress, iceberg lettuce, Bibb lettuce, and romaine lettuce.

Fermented Vegetables

Fermented vegetables are important probiotics, which are good to have in small portions daily. Sauerkraut, one of the most common, is easy to make. Making fresh fermented foods can really promote a healthy gut biome. There are good-quality commercial sauerkrauts on the market, but making it at home is a satisfying project.


Juicing and sprouting are quite popular now, particularly in warmer seasons and climates. Many advocates of juicing and sprouting live in Florida or Southern California, where refreshing foods make sense.

Sprouting is a good way of having salads and that light freshness in your diet all year round. Sprouting seeds or beans is, simply, germinating them. You rinse seeds to clean them and then soak them for up to twelve hours (depending on the type of seed). You drain the seeds and rinse at regular intervals. As the beans germinate, the nutrients are broken down and become more bio-available. The quality of the protein is improved, and the vitamin and fiber content is increased.

Sprouts can be used year round. Mung beans, alfalfa, broccoli seeds, and lentils are all easy to sprout. Add them to just about anything from soups to salads and grain dishes. Enzymes are the catalyst for proper food absorption. Living foods are loaded with live, active enzymes. Enzyme-rich foods boost energy, feed the cells, nourish the organs, tone the blood, regulate the bowels, and support immunity. Thus, living foods can help you beat fatigue and will make your skin glow.


Juicing has become popular as chewing has become unpopular. When you juice, notice the amount of pulp that is left behind. That pulp is part of the nutrient base of the food. Removing it challenges our digestion and wastes valuable minerals, fiber, and vitamins. Ecologically, economically, and from a health point of view, it is a wasteful process.


The nightshade family of vegetables is permeated with mythology. Nightshades include some plants with highly toxic features (such as tobacco and belladonna), and they also include potatoes and tomatoes, aubergine (eggplant), and peppers. Within that family of foods, there are chemical compounds that have a tendency to exacerbate inflammatory processes in the body.

Solanine is a toxic chemical found in members of the nightshade family, which is also known as the Solanaceae family. The chemical acts as a natural pesticide. Plants produce solanine to protect themselves from insects and fungi that attack them. Solanine and related chemicals have been found in potatoes, tomatoes, eggplants, red and yellow peppers, and other nightshade plants (but not in black pepper, which belongs to a different plant group). When creating a diet for someone who suffers from a major inflammatory illness, we eliminate all nightshades. On a health maintenance diet, I suggest that they be used sparingly and to make sure they are always well cooked.

Sea Vegetables

Sea Vegetables In some parts of the world, sea vegetables are traditionally consumed in moderate amounts regularly, to provide a balanced intake of minerals. We normally associate their use with Japan and Korea, but they were also part of the traditional Scottish and Irish diets. Let’s look at one sea vegetable. Kombu is a good source of iodine, which is necessary for proper thyroid function. Researchers in the United Kingdom found that it strengthened the gut mucus and slowed down digestion. It was also very low on the glycemic index and high in fiber. High consumption of sea vegetables (kombu) helps in the pre-digestion of pulses, which reduced the production of gas.

Seaweeds are low in fat, very low in calories, and rich in essential minerals, vitamins, and protein. Seaweeds are very beneficial to vegetarians and those abstaining from dairy foods because of their high levels of calcium, iron, and iodine. In addition to minerals, seaweeds contain vitamins, A, B, C, and E. All sea vegetables contain significant amounts of protein, sometimes as much as 48%. Nutrients in sea vegetables cleanse the colon and improve digestion and absorption. Research shows that the sticky starch in sea vegetables can strengthen gut mucus, slow down digestion, and allow food to release its energy slowly. Sea vegetables have an antibiotic effect on harmful anaerobic bacteria. Their unique range of polysaccharides removes pollutants, toxins, and heavy metals. Sea vegetables bind heavy metals and radioactive pollutants (deletion) (present in the environment from industry and transport) and remove them from the body.

Sea vegetables improve the full digestion and metabolism of nutrients from other foods, and they facilitate the formation of new cells. Harvard University has published a paper proposing that kelp (kombu and wakame) consumption may be a factor in the lower rates of breast cancer in Japan. Research is also being done on the effects of sea vegetables as an alternative to HRT. Sea vegetables are very high in lignins, plant substances that become phytoestrogens in the body—meaning that they help to block the chemical estrogens that can predispose people to cancers like breast cancer. Sea vegetables have traditionally been used in Asia to treat cancer, heart disease, and thyroid problems. The sea vegetables include nori (usually used in making sushi or as a condiment), kombu (used in making soup stocks or cooked with beans or vegetable stews), arame and hijiki (used as side dishes), and dulse (used with vegetables, in soups, or as a condiment).

It is important to check with distributors that all sea vegetables have been harvested from clean waters and have been tested for heavy metals. The same properties that sea vegetables have for attaching themselves to toxins in the body for excretion also make
it easy for them to absorb toxins in the water. This is the same as demanding organic growing for vegetables. There are many good sources, so do your homework.


Fruit “Eat more fruits and vegetables.” This is a familiar health message that blurs good nutrition lines in several ways. Fruit is high in sugar. This sugar (fructose) is not as disruptive to the system as the refined fructose we discussed earlier, particularly when consumed in a whole fruit, but it is still a simple form that is absorbed into the system quickly. However, at least fruit contains fiber, minerals, and vitamins, which slow down the potential negatives.

Sugar comes in several different forms: glucose, fructose, and sucrose. Glucose is the healthiest source of energy. Carbohydrates, such as those in grains and vegetables, break down into glucose, your body’s main source of fuel. Fructose is the only type of sugar found in fruits. When eaten in excess, it presents health challenges similar to those of the simpler refined sugars. Given the huge difference in sugar content from fruit to fruit, it’s almost impossible to suggest how much to consume. We should think carefully about our five a day.

People who cut back on all simple sugars for a month or two commonly become more sensitive to more complex forms of sugar in their food. Until then, people really do not perceive the sweetness in a carrot or in brown rice, partly because you have to chew in order for the sugars to begin breaking down. Also, the more we consume simpler forms of sugar (like fructose), the less we detect the sugars in other foods. So we need to reeducate our taste buds.

Fruits are, in general, are very perishable—so they are best eaten fresh and in season (and local, where possible). Tropical fruits are the highest in sugars and acid; fruits grown farther from the equator have less sugar. Drinking the juice of fruits is probably the worst form of consumption, since the sugars are more concentrated and the buffering agents have been removed. Sugars are also concentrated in dried fruits, so a raisin has more sugar content than a grape. Eating fruit in smaller amounts is generally a good idea. Fruit can also be cooked into purees, sauces, or baked. It makes great fillings for pies or as a smooth dessert dish. Think of fruit as a pleasure food, not an essential. There is nothing you can get from fruit that you cannot get from vegetables. It is a good idea to have fruit an hour or so after a meal, or between meals, for best digestion. Here are some nontropical fruits: apples, strawberries, cherries, blueberries, watermelons, cantaloupes, peaches, plums, raspberries, pears, and apricots.

Seeds & Nuts

Seeds and Nuts are an excellent source of protein and fat. When unshelled, they are easy to store for a long time. Once shelled, they are susceptible to rancidity if left at room temperature, unless preserved with salt. The oils in seeds and nuts complement grains and beans to provide the full range of amino acids needed to meet protein needs; and they also contain easily assimilated and healthy oils. They may be used as condiments with grains or vegetable dishes or roasted as a snack. Roasting nuts and seeds releases their oils, making them easier to digest.

Nuts and seeds are an excellent source of fats in a healthy vegan diet. They contain healthy mono- and polyunsaturated fats—fats that manage inflammation, maintain the normal structure of our cells, and lower cholesterol. Extensive research associates nut
consumption with a lower risk of coronary heart disease (CHD).430 Allergic reactions to nuts principally affect young children, and these may be severe or even life-threatening. They are caused by allergenic seed storage proteins. A smaller number of people have allergic responses to seeds. Possible symptoms of these allergies are hives or swelling, trouble breathing, tightness of the throat, nausea, abdominal pain, and diarrhea.

Less than 1% of the population has a peanut allergy. The symptoms can vary between mild to severe. Generally, those with allergies are allergic to several foods, the most common being milk, eggs, shellfish, and wheat. Between 1997 and 2008, the number of children reported with nut allergies more than tripled. This has run parallel to an increase in cases of asthma and eczema. Most adults with allergic reactions have had them since childhood. The tree nuts—such as macadamia, cashew and brazil nuts, hazelnuts, pecans, and walnuts—all have a high fat content. The walnut and hazelnut are native to Europe. All tree nuts originate in subtropical climates—except pecans, the only native North American tree nut. Chestnuts are used in many parts of the northern hemisphere and have the least fat of any nut; they are rich in carbohydrates and the only nut that contains vitamin C.

Peanuts have among the highest amounts of oil in this group. They are from a different botanical family than true tree nuts but are commonly thought of as a nut. They are widely used as a snack item or as an ingredient in snacks, for their oil, or as animal feed. A handful of any of the tree nuts supplies more than the daily requirement of healthy fats.

Seeds are often used as a garnish on foods, particularly with whole-grain dishes. Pumpkins seeds, sesame seeds, sunflower seeds, chia seeds, flaxseeds, and hemp seeds are all sources of omega oils and add flavor and variety to the diet.

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