Bioactive compounds are substances in food that offer health benefits beyond the traditional roles of macronutrients and micronutrients. While much public attention focuses on the beneficial compounds found in plants, known as phytochemicals, animal foods contain their own set of unique, health-promoting substances. These animal-sourced compounds contribute significantly to human physiological function, often supporting energy production, cognitive health, and muscle integrity. A deeper understanding of these substances reveals what they are called and why they play a distinct and important role in human nutrition.
Naming the Health-Promoting Compounds
The scientific community uses the term “zoochemicals” to describe these natural, non-nutrient chemicals found in animal-based foods. This term is directly analogous to “phytochemicals,” using the prefix “zoo,” which refers to animals. Zoochemicals are defined as compounds that are physiologically active and provide a benefit to the body beyond simply supplying calories, vitamins, or minerals.
More broadly, these substances are often referred to as “Bioactive Animal Nutrients.” This category includes compounds that the body can synthesize on its own but not in sufficient quantities, making dietary intake from animal sources a biological necessity. These compounds are typically concentrated in muscle tissue, organs, and eggs.
Profiles of Essential Bioactive Nutrients
Creatine is one of the most studied bioactive compounds found in meat and fish, playing a central role in cellular energy metabolism. It is stored in muscles as phosphocreatine, which rapidly regenerates adenosine triphosphate (ATP), the body’s primary energy molecule during high-intensity activity. This function supports muscle strength, mass, and cognitive function.
Carnosine is a dipeptide, synthesized from the amino acids beta-alanine and L-histidine, and is concentrated in skeletal muscle and the brain. It acts as an intracellular pH buffer in muscle cells, helping to reduce the acidity that causes fatigue during intense exercise. Carnosine also exhibits significant antioxidant properties, scavenging reactive oxygen species.
Taurine is an amino sulfonic acid abundant in the heart, brain, retina, and muscle tissue, and is primarily sourced from meat and seafood. It supports cardiovascular function by regulating the force of heart muscle contractions and maintaining proper osmolality within cells. Taurine also functions as a neurotransmitter, supporting the stability of cell membranes.
Choline is an essential nutrient crucial for maintaining the structural integrity of cell membranes, specifically as a precursor to phospholipids like phosphatidylcholine. It is used to produce the neurotransmitter acetylcholine, which is involved in memory, mood, and muscle control. Choline is also required for lipid transport, helping to prevent fat buildup in the liver.
Heme iron is the form of iron bound within a porphyrin ring structure in hemoglobin and myoglobin, unlike the non-heme iron found in plants. This compound is critical for oxygen transport in the blood and is integral to various enzymes involved in energy production. Heme iron is exclusively found in animal tissues and is recognized for its superior absorption.
Why Animal Sources Offer Unique Nutritional Value
Animal-sourced foods provide a distinct nutritional advantage primarily due to the high bioavailability of their compounds. Bioavailability refers to the proportion of a nutrient that is absorbed and utilized by the body after consumption. For example, heme iron from meat is absorbed at a rate of approximately 25%, whereas non-heme iron from plant sources is absorbed at a much lower rate, often 17% or less.
This difference in structure and absorption means that even though a plant food may contain a high quantity of a nutrient, the body may only be able to access a small fraction of it. Furthermore, animal products are the virtually exclusive natural source of Vitamin B12, a compound necessary for nerve function and DNA synthesis. This vitamin is highly bioavailable from animal sources and cannot be reliably obtained from unfortified plant foods.
The functional necessity of these compounds also differentiates animal sources from plant sources. Creatine, for instance, is the immediate precursor for the phosphocreatine energy system, a mechanism that cannot be replicated by plant-derived nutrients. Similarly, zoochemicals like carnosine and taurine are either absent or present in negligible amounts in plant-based diets.