Here is a ton of research in a tiny nut shell:

The top reason I can think of to garden organically is to avoid toxic chemicals.

Chemical toxins are harmful to the organic human body. There are over 600 active chemicals registered for agricultural use. The EPA approved these toxic chemicals before little if any testing was ever done as to the effects on humans. Billions of tons of toxic chemicals are used agriculturally each year. Approximately 16lbs of toxic chemicals are ingested per person per year. That would be assuming no one eats organic so actually if you do not eat organic you are probably consuming more than that because you are picking up the count for those of us who do.

Illnesses due to toxic chemicals used in food as identified in medical research include adult and child cancers, numerous neurological disorders, immune system weakening, autoimmune disorders, asthma, allergies, infertility, miscarriage, and child behavior disorders including learning disabilities, mental retardation, hyperactivity (ADHD) as well as altering hormones essential for maintaining healthy bodily processes. Petroleum based chemicals are believed to cause these problems by a variety of routes including – impairing proper DNA (Gene) expression, weakening DNA Repair, accelerating gene loss, degeneration of the body’s detoxification defenses (liver and kidneys) as well as gradual weakening of the brain’s primary defense (the Blood Brain Barrier).

Petroleum based pesticides have been in use since 1950.

Also, to avoid GMO foods

GMO (genetically modified organisms)

The American Academy of Environmental Medicine (AAEM) urges doctors to prescribe non-GMO diets for all patients. They cite animal studies showing organ damage, gastrointestinal and immune system disorders, accelerated aging, and infertility. Human studies show how genetically modified food can leave material behind inside us, possibly causing long-term problems. Genes inserted into GM soy, for example, can transfer into the DNA of bacteria living inside us, and that the toxic insecticide produced by GM corn was found in the blood of pregnant women and their unborn fetuses.

GMO crops have been made to be “Round-Up” resistant so that even more chemical pesticide can be sprayed onto the crops without crop damage. In other words  not only may you suffer the damage from GM food itself but also the compounded damage from even more toxic chemicals being used with it.

I have only sited the direct illnesses here as found in research studies. The body gets bogged down trying to process toxic chemicals that are not only ingested but also inhaled and absorbed. The immune system is greatly compromised as valuable energy is preoccupied with processing these chemicals.  That same energy may be needed elsewhere to stave off biological attackers. The result may be sickness such as flus etc. that otherwise might have been fought off.

The prettier side of gardening organic is to obtain more nutrient rich food and experience better flavor.

Conventional big farming practices break down soil and kill nutrients. It is then added back in the form of chemical fertilizers which then become present in the food grown in them and are toxic to the human body.

Organic gardening practices constantly amend and build nutrient rich soil. Food grown in nutrient rich organic soil is much richer in the organic nutrients that nourish, heal and protect our bodies and there is no toxicity.

Organic foods are also known to be much more flavorful than conventional. I have been eating organic for more than 12 years. In my opinion most conventional fruits, vegetables  and greens are greatly laking in flavor.

We are all made subject to ugly environmental toxins but we do have the power to choose to reduce our exposure greatly and give our bodies more than a fighting chance. Gardening and eating organic achieves that goal.

These are the personal reasons to garden and eat organic. Environmental reasons, there are many,  will have to be a whole other blog.