Why This Matters for the Animals in Our Care
Most people are familiar with Monsanto’s Roundup, the world’s most widely used weed killer. What is less widely known is that glyphosate, the active ingredient in Roundup, is often sprayed directly on wheat, oats, lentils, peas, and other crops shortly before harvest. This practice, called pre-harvest desiccation, began in the 1980s and helps dry crops more quickly and uniformly.
Over the years, glyphosate residues in food have become increasingly common. For example, the U.S. Wheat Quality Council found detectable glyphosate in every flour sample tested. Similar findings have appeared in surveys of oats, barley, and many pulse crops.
Potential Health Concerns
Glyphosate has been the focus of considerable scientific debate. The International Agency for Research on Cancer classifies it as a probable human carcinogen. Research has shown that glyphosate may act as an endocrine disruptor, affect beneficial gut bacteria, and cause oxidative or DNA damage in certain human cell lines.
While regulatory agencies differ in their interpretations, concerns remain about the possible effects of long-term, low-level exposure—especially for animals consuming the same food daily for years at a time.
Organic crops are not supposed to be treated with synthetic desiccants, but contamination from drift or shared equipment has been reported.
Crops Frequently Desiccated With Glyphosate
Many ingredients commonly found in human foods and pet foods may be desiccated before harvest, including:
- Lentils
- Peas
- Chickpeas
- Non-GMO soybeans
- Flax
- Rye
- Buckwheat
- Millet
- Triticale
- Canola
- Potatoes
- Sugar beets
Because these crops appear widely in commercial pet foods, daily dietary exposure for dogs and cats can be significant.
How Grain-Free Pet Food Changed the Market
Grain-free dog and cat foods rose to popularity in the late 1990s and early 2000s. Marketing campaigns suggested that grains were unnatural for pets and that diets based on peas, lentils, and potatoes were healthier and more biologically appropriate. By 2015, grain-free sales had grown by $2.7 billion, reshaping the pet food industry.
At the time, I owned a health food store for people and pets. When I saw grains being replaced with large amounts of legumes and potatoes—used largely because starch is necessary for kibble production, not because it is nutritionally ideal—I made a prediction: if pet owners fed these diets exclusively, without rotation or fresh food, health issues would eventually follow.
Unfortunately, this appears to have happened. Over the past decade, veterinary cardiologists have investigated an increase in diet-associated Dilated Cardiomyopathy (DCM) in dogs consuming certain legume-heavy diets. The exact cause remains under study, but concerns include:
- Amino acid imbalances affecting taurine status
- Nutrient-blocking compounds naturally found in legumes
- Poor protein bioavailability when legumes dominate the formula
- Potential cumulative exposure to agricultural chemicals such as glyphosate
None of this means that lentils or peas are inherently harmful. The issue arises when they become a major daily component of a dog’s or cat’s diet—especially when the diet never varies.
Why Daily Lentil and Pea Based Diets May Be Problematic
Dogs and cats rely heavily on animal-based proteins for optimal health. When their diet depends too heavily on lentils, peas, chickpeas, or potatoes:
- The amino acid profile can be unbalanced unless corrected through supplementation
- Anti-nutritional compounds in legumes may impair absorption of essential minerals
- Long-term exposure to chemical residues may accumulate over time
- Slow-developing nutrient deficiencies may go unnoticed until advanced
- Eating the same formulation every day magnifies any nutritional shortcomings
For animals who consume one diet continuously, these issues can compound over the years.
Coming Next Month
The more we learn about modern agricultural practices, the more empowered we become to advocate for our own health and the health of the animals who depend on us. While the prevalence of glyphosate in our food system is concerning, there are practical steps every pet parent can take to reduce exposure.
In the next issue, we’ll explore how to evaluate pet food labels, avoid common pitfalls, and choose safer, species-appropriate diets for the animals we love.
Wishing serenity and peace, Jo Bighouse