Science is a process sometimes described as “an ever-widening darkness.” Everything learned serves to shed light on what is still unknown and what needs to be learned next, how better to re-ask the question considering recent insight.
Nutritional requirements for dogs are put up by hardworking professionals who are civic minded enough to donate time to essential committee work. They are willing to take a stand, exposing themselves to critique, knowing how essential it is we have a benchmark to change from.
It’s easy to point out where you think the official guidelines published by the authorities are inadequate, misinformed, or wrong. And you should. But this must always be done with respect and humility. Committee members have the courage to take a stand, knowing that is how science works. We roll forward with our best thinking today, always open to a better or more useful guess.
The result is that while Minimal Daily Requirements can be useful … there is fine print that must be considered.
The Standard Approach
In discussing diet design and formulation, nutritionists express a given nutrient’s need in terms of the minimum daily amount required to prevent deficiency. This construct is seen in every aspect of the field, in human nutrition from infant to geriatric, and in animal nutrition from cows to pets.
The common term is MDR or minimum daily requirement. A container of vitamin pills for humans lists for each vitamin how much of the daily requirement is provided by the pill. Each species of food animal has an august committee convened to list requirements for all known nutrients, from protein in grams to selenium in parts per million, each in daily amounts. The pet food industry is obsessive about AAFCO nutrient requirements for dogs, a list of all important nutrients needed on a daily basis.
But this is misleading … because it’s not what happens in nature.
In the primordial world where all creatures evolved for hundreds of millions of years, and were perfected to thrive, no nutrient was ever available on an even, steady daily basis. As a matter of fact, the norm was long periods of lack with short intervals of relative abundance.
Blueberries with their delightful hit of flavonoids were plentiful for two weeks and then gone. Some mushrooms are a bonanza of vitamin D, but only ripen for a few weeks during the year. Even in tropical forests, plants bloom intermittently, not constantly. The typical predator goes days between successful hunts.
The Gift Of Adaptability
In all biology, metabolism, perhaps especially human metabolism, is perfected to adapt to intermittent nutrient availability. Bones serve as a savings account for calcium when intake is low. The liver stores vitamin A for when it is not in the diet. Scurvy, the ancient curse of sailors, is a vitamin C deficiency that took four to six months of inadequate diet to set in … and a diet with tropical fruit soon repaired it.
Our genetic machinery is exquisitely adapted to deal with lack. It is replete with backups and redundancy.
All known enzymes have a primary function, as well as secondary capacities that serve to cover for a critical enzyme gone missing. We can store excess nutrients for use during possible future lack. For millions of years, the wolf, coyote, dingo, fox, tiger and cougar thrived and prospered without the first microgram of store-bought vitamin, in blissful ignorance of our yardstick of MDR.
Carbohydrates In Nature
The primordial world has another distinction, both in the past and where it yet exists today. It is very hard to find carbohydrate in the wild – that is to say, starch and sugar. Modern agriculture made carbs easy to find. On a natural or primordial diet, gut contents are low in carbs, thus high in bacteria that thrive in the absence of carbs. These bacteria have numerous nutritional and immune benefits, including making B vitamins.
Pet food companies are required to provide total caloric content of their product on the package. Much more useful would be the percent of these total calories derived from fat, protein and carbohydrate.
It is possible for a diet of 3000 calories to be less fattening than one of 2000. While fat quickly ramps up numeric caloric density of a diet, it is innocent in causing fat. Obesity is caused by carbs, not fat. Showing the source of the calories would provide more useful information.