Is a Plant-Based Diet Always Nutritious?

You decided to explore a plant-based diet, go vegan, or simply incorporate more healthy vegetables into your meals.  This is terrific and will have tremendous positive impacts on your health.  Or will it?

Yes, any plant-based meals will have a tremendous impact on overall health. But there are some facts that are often overlooked and need to be very strongly considered…

  • Where are you getting your ‘healthy’ vegetables from?
  • How does the source of your vegetables impact the nutrition found in them?  
From Seed to Plate

Let’s take a tomato grown on a farm and follow it from the seed to your plate.  The tomato seed is grown in soil or water somewhere in the world.  It is fed some type of fertilizer or food to enhance its growth and potentially sprayed for bugs.  The processes used to fertilize and spray may be organic or may not be organic.  The tomato is harvested, transported, and then placed on your grocery story display. Think about the timeline of this process, especially if your tomato was grown in a foreign country or in a US state far from yours. This process is lengthy and the timeframe from harvest to your actual plate and mouth is also significant.  So what happens to the nutritional value of that tomato once it is removed from its plant source to the time it gets inside your mouth?

Disappearing Nutrients

Nutrients in fruits and vegetables start to break down after they are removed from the plant during harvest. The three natural destroyers of nutrients in fruits and vegetables are heat, light, and oxygen.

So what actually causes the vegetable and fruit nutrients to break down after harvest?

We need a little bit of science class to help us understand what is happening when a fruit or veggie is harvested.  After harvest, that fruit or vegetable is still alive. It continues to breathe, a process known as respiration.  Respiration breaks down stored organic materials, such as carbohydrates, proteins and fats, and leads to the loss of food value, flavor and nutrients. Produce will lose heat from this respiration as well as moisture, which is the way nutrients are lost. Warm, dry air can speed up this process considerably. Asparagus, broccoli, mushrooms, peas and sweet corn have a very high respiration rate and will lose nutrition and flavor more quickly than apples, garlic or onions, all of which have low respiration rates.

Enzymes in plants also cause loss of nutrients and color, as well as flavor changes. Enzymes continue to change the composition of produce. If you cut an apple and expose it to air, you will notice that it turns brown, or oxidizes. This color change is the result of enzymes. The browning is a sign that the nutrient value is also decreasing.

Another potential source of nutrient loss has to do with whether produce was ripe at the time it was harvested. A tomato can be harvested before it is fully ripe and will turn full color when left on the window sill. However, it will not attain the highest nutrient levels, according to the Harvard Medical School Center for Health and the Global Environment.  It must be harvested when ripe to have the highest nutrient levels.

How can you help your fruits and vegetables to retain their nutrients after harvest?

This loss of nutrients can be minimized by proper storage, processing and cooking. However, the most impactful way to retain the nutrients in your fruits and vegetables is to BUY LOCAL!

Here are a few techniques used to help retain nutrients in fruits and vegetables:

  • Limit storage time. Fresh is best when it comes to taste and nutrition.  Buy local so you can easily replenish your produce.  The Harvard Medical School Center for Health and the Global Environment recommends choosing produce that is as fresh as possible. If you can’t start your own garden then shop a local farm.  
  • Store most fruits and vegetables in the refrigerator to slow spoilage. Some fruits and vegetables should not be placed in the refrigerator. Tomatoes are one of those as their flavor is destroyed in the refrigerator. Tomatoes should be held at room temperature.
  • Minimal cooking. Steam vegetables briefly until just crisp and tender. For example, asparagus and broccoli should retain their bright green color. Water-soluble nutrients are destroyed with prolonged cooking time.
  • Avoid cutting vegetables too far in advance. When we slice into a vegetable or fruit, we expose the cut surfaces to heat, light, and oxygen which destroys the nutrients. Wait to slice foods until you are ready to cook and eat them.

Soil Impacts Nutrition and Plant-Based Diets

Preserving further degradation of a vegetable or fruit’s nutrients once harvested is one thing we need to do in order to retain as much nutrition in our vegetables and fruits.  But I have one more question.  How do we know that the fruit or vegetable was actually grown to the maximum nutritional potential that is often quoted on nutrition labels?  If a tomato says it has 10% Vitamin C, does it really have 10% Vitamin C?   Does soil and the health of the plant impact the nutrient potential of a fruit or vegetable?  According to the Bionutrient Food Association, it does! And you can taste it!

Nutrient density, as defined by the Bionutrient Food Association (BFA), is “when you have greater levels of nutrients per unit calorie in a crop, better flavor, better aroma, and better nutritive value.” According to Dan Kittredge, Executive Director of BFA, “the compounds that correlate with nutrition, flavor, and aroma in crops, are built from the soil and through a well-functioning microbial ecosystem. The bacteria and the fungi in the soil are fed by the plants. When the plant makes sugar in the leaves, it injects that sugar into the soil to feed the soil life, who then digest the soil and feed the nutrients up to the plant. When you have a well-functioning soil life that is flourishing with vitality and life, you will get plants that have access to the nutrients necessary to have nutrient dense crops.  Tillage, bare soil, adding fertilizers, fungicides, and insecticides are counterproductive to nutrient density in crops which is why the USDA and other sources report about the decreasing levels of nutrition in food. When plants are healthier, they are more productive, they have better pest and disease resistance.  We can then reduce the need for fungicides, insecticides, and fertilizers.”

How HeartBeet Farms Supports Your Plant-Based Diet

At HeartBeet Farms, we believe wholeheartedly in what Dan is conveying.  We are focused on optimizing the nutritional value of the produce that we are growing. We do not till our soil, we constantly add required nutrients to our soil, and we do not keep our soil bare. We grow cover crops or cover with leaves, compost and straw.  Most importantly, we are committed to continuous learning from fellow farmers such as Dan Kittredge of BFA, Craig Floyd of the Giving Garden in Mystic, CT, and Patty Gentry of Early Girl Farm in Bellport, NY.  And most of all, we do our best to listen and respect the most knowledgable farmer, Mother Nature!

Our primary message from HeartBeet Farms – especially if you are focused on a plant-based diet – know where your food comes from and buy as LOCAL as possible….local farmers need you and so does our Earth!

Articles used for reference:

Maximizing the Nutritional Value of Fruits and Vegetables

How Long do Fruits and Vegetables Retain their Nutrients

How do Fruits and Vegetables Lose Their Nutrients After Picking