Story at-a-glance -

• The Cavendish variety of banana is poised to be struck down by an insidious fungus that has infected soil in Australia, Asia, Middle East, Africa and the Americas
• In an effort to maintain this variety, researchers have begun to edit its genome. Producers are aiming at a genetically altered plant able to pass regulators, which happened earlier in the U.S.
• It is not surprising that without diversity any type of crop may be vulnerable; however what appears to be progress with genetic engineering may actually be a step backward in terms of health
• The Cavendish is only one of nearly 1,000 varieties of bananas. In a move that may seem counterintuitive, you may wish to consider eating unripened green bananas as they are a great source of prebiotic fiber

The humble banana, one of the most popular fruits in the world, is big business. The banana is tasty, inexpensive and comes in its own protective case. The fruit is picked while still green as it's fully capable of continuing to ripen off the tree. Bananas do best when stored at room temperature since they change color and become mushy when the temperature drops.

Although high in vitamin B6, fiber, potassium, manganese and vitamin C, the banana is also high in carbohydrates. If you include this fruit in your diet, take care to limit your intake, especially if you are insulin resistant, deal with metabolic syndrome or have Type 2 diabetes.

The United Fruit Company (UFCO), which later became Chiquita Brands International, was founded in 1899. Growing operations were based in San Jose and Costa Rica. Until then, bananas were relatively unfamiliar in the U.S. UFCO diversified its product line to include pineapples, tomatoes and cantaloupes, which helped grow the company.

Fungus May Wipe Out Conventional Bananas

The first banana variety sold in the U.S. was the Gros Michel, which was struck down by the TR1 fungus. Farmers had a backup banana species, the Cavendish, which was resistant to TR1 and resilient enough to withstand export, transport and delivery. By the 1960s, the Cavendish was making its mark in the U.S.1

Much the same is happening again. In August 2019, the Colombian government confirmed that TR4, another banana killing fungus, is growing rampant in the Americas. This is especially problematic considering that growers in this part of the globe are major contributors to the world's banana supply. This situation has created a race to genetically engineer a fruit to withstand the fungus.

When the Cavendish was selected to replace Gros Michel, it was chosen because it was naturally resistant to TR1. Currently, there are no alternative banana varieties resistant to TR4. Several teams are employing genetic alterations to save the banana crop.

Using breeding methods to modify the Cavendish is not possible, as the variety is sterile and propagated only by cloning. Since it represents 99% of global banana sales, scientists are turning to the gene editing tool CRISPR to change the Cavendish banana’s resistance to TR4.

To date, researchers have not found any fungicide capable of killing the fungus and have determined it is able to live in the soil for up to 30 years. It first appeared in Asia before traveling to Australia, the Middle East, Africa and now the Americas.

In an effort to appease regulators who are opposed to the insertion of foreign material into the fruit, the same Australian team is using CRISPR to edit the banana’s genome. This option is in its early stages so it will likely take several years before field trials get underway.

Scientists in Australia have also inserted a gene into the Cavendish and are field testing these against TR4. Another team in Nairobi is using CRISPR to suppress genes in the banana in the hope this will make it resistant to the TR4 fungus. Again, this is in early trials and has only been accomplished on tissue in a lab.

Are You Ready for Genetically Modified Bananas?

Scientists and the banana growers are putting most, if not all, of their eggs into the CRISPR basket, banking on the banana getting past regulators and onto grocery store shelves. But it’s not clear how regulators around the world will react to a gene edited banana being sold in their country.

If past actions and statements are an indication, then it’s helpful to know Chile, Brazil, Israel, Columbia and Japan have all released official statements they may be lenient as they consider whether the genetically modified fruit could enter their country. In 2016, the U.S. Department of Agriculture (USDA) made the decision not to regulate a genetically altered organism commonly found in the grocery.2

A white-cap mushroom had been genetically modified using CRISPR, which the USDA said could be grown and sold without passing through any regulatory agency in the U.S. A research scientist at a Chinese academy, who was not involved in the mushroom study, believed this decision would be well received by the research community.

The scientist said it was likely an indication that other genetically modified foods would fall “outside of regulatory authority.” The mushroom was one of 30 other genetically altered organisms — mostly plants — that had successfully sidestepped any regulation by the USDA. However, it was the first to have used CRISPR to accomplish the genetic modification.

The USDA stated the mushroom didn’t fall within their purview as the mushroom’s genetic code was altered, but no foreign DNA was inserted. When the USDA regulations were developed in the 1980s, foreign DNA was necessary to alter the genetic code of plants.

However, newer techniques avoid this path while still genetically altering the plant’s DNA expression without any knowledge of the long-term consequences to human health. Plant geneticist Rodomiro Ortiz from the Swedish University of Agricultural Sciences knows there is no easy answer to developing a variety of banana resistant to TR4. However he warns against the sole focus on biotechnological solutions.3

He points out there are more than 1,000 varieties of bananas producers could choose from to create a market, saying: “We should tap into the diversity available and have a marketing campaign that says you can enjoy the banana in other ways.”

Identical Cavendish Bananas More Vulnerable to Disease

It is not surprising that a monoculture crop with no diversity would ultimately fall prey to a fungus. Monoculture crops have led the faster, bigger and cheaper approach to food, which is slowly draining the planet's resources and compromising your health. Large attacks by pests and fungi are ultimately related to the lack of diversity in the soil and in plants.

As I've written in the past, we've lost 75% of the world's crop varieties in the past century. Genetically engineered (GE) crops are speeding this destructive process, in combination with the 100 million tons of herbicides that have been dumped onto crops, polluting soil and streams.

These actions alter the composition of soil bacteria and set up a system much like your gut bacteria, where harmful organisms are allowed to grow unchecked. Agriculture is a complete system based on interrelated factors. Anytime you change one part, it changes the ability of the other components to work together.

In other words, it is impossible to change even one minor aspect of a system without altering the entire system. This is partially why GE crops are not a viable alternative.

Just as agriculture is a system depending upon smaller systems, so are food security, health, environmental stability and democracy. They are all interrelated. As one changes, it affects the others. Creating monocultures has increased production at a significant cost to health and with an enormous toll on the environment.

In short, what appears to be progress on the surface is really a step back in terms of long-term food security and overall health. Although the Cavendish banana is the most common variety, it is not the only one. Others differ in terms of taste and firmness as well as in their options for use when cooking. You'll find a list in my past article, “All You Ever Wanted To Know About Bananas.”

Benefits of a Fiber Rich Diet

Ripe bananas are full of carbohydrates that metabolize into sugar. While tasty on occasion, limiting your net carbohydrates is an effective way to reduce your risk of metabolic syndrome, heart disease and many other ailments. You can calculate your net carbs by subtracting your net fiber intake, in grams, from your total carbohydrates, in grams.

After carbohydrates are metabolized and released as blood glucose, insulin is released from your pancreas. Insulin transports blood glucose into the cells, after which you may suddenly find yourself hungry, sometimes close to your last meal.

Reaching for a high-sugar, carbohydrate-laden snack perpetuates the cycle of high blood sugar, insulin release, plummeting blood sugar and ultimately reaching for another snack.

On the other hand, eating foods high in fiber, such as vegetables, will reduce your cravings and help keep you feeling satisfied and full for longer periods of time. This combination will also help you control your weight.

Fiber and fat increase your body's opportunity to burn fat for fuel, which creates fewer harmful reactive oxygen species and secondary free radicals responsible for damage to cellular and mitochondrial cell membranes. As you become an efficient fat burner, it improves your odds of living longer, improving your glucose metabolism and reducing inflammation.

Benefits of Digestive Resistant Starch in Unripened Bananas

While fully ripened bananas are high in carbohydrates, when unripened they are high in fiber. Other fruits that are high in fiber when consumed unripened include papayas and mangoes. It appears their nutritional content changes depending on their state of ripeness. The more unripe they are, the higher the amounts of digestive resistant starch they contain.

Although it may seem counterintuitive, a piece of unripened fruit may be healthier than a ripened one. Fiber is first classified as either soluble or insoluble. The fermentability of fiber is another factor that is important to health. Digestive-resistant starches are low viscous fibers that ferment slowly in your large intestine. They act as prebiotics to feed healthy bacteria and help them thrive.

Since they ferment slowly, they don't make you gassy and will add significant bulk to your stool. When the fiber is indigestible, it does not spike your blood sugar and may help improve insulin regulation.

Before a banana ripens, 80% of its dry weight may be composed of starch. The amount of resistant starch decreases as the banana ripens. This high level of digestive-resistant starch makes green bananas a safe treatment for diarrhea in children and adults.

Although the taste and texture of an unripe banana is not often appreciated, if prepared properly it can be tasty. See my past article, “The Surprising Health Benefits Of Unripe Banana, Papaya And Mango,” for recipes using unripened versions of these fruit.