29 January 2024 Connecting plant, animal and human health

The old adage we are what we eat has taken on new meaning – we are what we eat eats – thanks to a pair of Lincoln University researchers, who have identified a clear link between a modern and innovative grazing management approach for cattle and significant health benefits for humans.

The new research, funded by Lincoln University Centre of Excellence – Designing Future Landscapes, Silver Fern Farms and Fertilizer New Zealand, is the very first of its kind worldwide.

The research outcomes, as announced by Professor Pablo Gregorini and Dr Anita Fleming, demonstrated that beef cattle which were grazed under a functional diversity grazing regime, i.e. allowed to choose their own diet from a selection of five separate strips of monoculture plant species (Adjacent Monoculture Strips orAMS), recorded up to 15% higher average daily weight gain and greater meat colour than cows grazing a conventional ryegrass-based pasture (Perennial Ryegrass or PRG) or those grazing a complex multispecies (30 species) mixture (CMS).

Meat from the test animals was then consumed as cooked beef patties in human trials conducted at Lincoln University over a period of six weeks, with the participants’ blood tested at intervals of zero, three and five hours after each meal.

“The results were compelling,” said Professor Gregorini, who heads Lincoln University’s Centre of Excellence – Designing Future Productive Landscapes and the Lincoln University Pastoral Livestock Production Lab.

“Blood samples taken from the trial participants who ate the AMS beef showed that their metabolisms were advantageously affected by consuming the test beef in myriad ways, but most significantly by the increased presence of Vitamin E (Gamma tocopherol), Hydroxymethylglutaryl and Arginine.

“Vitamin E is a known potent antioxidant and anti-inflammatory and has been identified as a colorectal cancer chemopreventive agent, as well as being superior to α-tocopherol in its ability to reduce cancer cell growth.

“Hydroxymethylglutaryl is also known as statins, and is used adjunctively with diet and exercise to treat hypercholesterolemia by lowering total cholesterol.

“Arginine is used by the body to help build muscle and rebuild tissue, and it also helps to keep the blood vessels open.”

Professor Gregorini added that the blood test results also revealed a reduced presence of Indoxyl sulphate.

“Indoxyl sulphate is a uremic toxin accumulating in the plasma of chronic kidney disease patients. Accumulation induces side effects in the kidneys, bones and cardiovascular system.”

Professor Gregorini further added, “Dr Anita Fleming’s experiments also show that the benefits to the human metabolism of eating the AMS-fed beef were evident after just one meal.”

Underpinning the groundbreaking research is the discovery that the specific metabolomic properties of the five plant species grown in the AMS strips, when foraged by the cows in discrete quantities per their individual choice, in turn positively affected the metabolisms of the cows.

Professor Gregorini continued, “It’s not only the menu, but also – and more importantly – how we set the table for them!

“Our research describes the interrelationships between plant, animal and human health in a measurable way, and unambiguously demonstrates the beneficial human health outcomes of eating higher-welfare food products.

“It’s not enough simply to say, ‘we are what we eat’. In fact, we are what we eat eats!”

The Lincoln research team also conducted trials with dairy cows, sheep and deer using the AMS grazing system, (aka functional diversity), achieving similar results regarding the animals’ performance, environmental impact and welfare. They have a massive reduction in nitrogen excretion and in simple terms, if they are finished faster, they produce less methane. If they produce more milk at the same intake they have production intensity.

While human trials have yet to be undertaken with milk and venison, a human trial with the test subjects eating lamb has recently finished. The Lincoln researchers expect to demonstrate similar gains in human health, as metabolomic profiles on milk and venison show similar patterns as beef.

Dr Anita Fleming believes the Lincoln team’s research, which powerfully demonstrates the interrelationships between plant, animal and human health, offers farmers an opportunity to realise significant productivity gains with a relatively modest on-farm investment.

“Our research shows that by simply planting pasture in monoculture strips of common plant species that are already widely available, and allowing the animals to graze freely, to have ‘functional choice’, farmers will not only enhance the welfare of their stock, including increased weight gain rates, but will also realise greater value from their product.

“More than ever, domestic and international consumers are demanding food products that are healthy and ethically and sustainably grown.

“Farmers in Aotearoa who adopt the AMS grazing system will enjoy the competitive advantage of marketing product that promotes human health and enhances animal welfare while at the same time safeguarding the environment.”

Professor Gregorini says, “Ultimately, our health reflects the way we graze our animals and how we manage and care for the landscapes we all inhabit.”

For media enquiries email media@lincoln.ac.nz or phone 03 325 3827