We worry over cortisol in humans. Cattle deserve our attention too

By -

Durga Sreenivasan

Dairy farmers must identify and rectify the buildup of stress and resultant cortisol, so their cattle aren’t on permanent survival mode

0:00

May 27, 2026

min read

Dont miss out on monthly updates

Though milk and dairy products are cornerstones of Indian cuisines and nutrition, we seldom stop to think about the food and agricultural systems that bring them to our kitchens and dinner plates. The welfare of the animals at the centre of these systems, their ability to walk and loiter freely, to choose when and what they will eat may sound like small freedoms, but they are important determinants of cattle health.

To the still-ambivalent reader, I offer a more personal, selfish reason to care about this aspect of domestication: livestock well-being affects milk composition, and by extension, the health and nutrition of the milk you consume.

The most widely accepted way of measuring this stress is to test for the concentration of cortisol, the dominant stress hormone in cattle.

Like humans, livestock respond to stress through changes in hormones secreted. Hormones secreted into the bloodstream of distressed cattle cross right over into their milk, and consequently, into our stomachs. India is the world's largest milk producer, and the steadily increasing demand for dairy only poses greater risk to cattle, owing to the prevalence of intensive, stress-causing practices.

Measuring stress in tangible ways

Cattle express stress in various ways. For instance, ruminating (the act of regurgitating swallowed food and chewing it again) is a natural behaviour essential for digestion, only undertaken during rest periods. When stressed or unwell, the time spent ruminating reduces. Vocalisations—the various bellows, grunts, and moos of cattle—also reveal their emotional state. Higher frequencies, lower pitches and reduced intensity of vocalisation are all associated with higher stress. The most widely accepted way of measuring this stress is to test for the concentration of cortisol, the dominant stress hormone in cattle.

Like humans, livestock respond to stress through changes in hormones secreted.

Cortisol is a hormone found in most mammals, including humans. Ordinarily, it performs a host of constructive functions to support immunity, reproduction, inflammation, and most famously, the stress response. Chronic stress elevates cortisol levels for extended periods of time. Stress in cattle can stem from factors like heat stress and disease, or management practices like being housed in compact spaces, or not having ready access to drinking water. If not identified and rectified, this stress essentially puts the cattle on survival mode permanently. The protein in their muscles breaks down, bones start decalcifying, and some cattle undergo neural degeneration too. Needless to say, the cattle's productivity falls too.

Also read: Understanding the social behaviour of buffaloes, a sensitive species

Cortisol you didn’t ask for

Stress-free cattle, thus, is in any dairy farmer's best interests. Why should it concern a consumer? It changes the nutritional profile of the milk, markedly reducing its fat, protein, and lactose content.

Unlike bacteria, cortisol is unaffected by sterilisation or pasteurisation. So, with your spoonful of creamy curd, you may be getting a dash of cortisol that you didn't really sign up for.

Also read: Buffalo domestication: How housing conditions in rural, urban India affect welfare

Conscious consumption = prevention?

So, how do we know if the milk we are drinking is cortisol free? Put simply, we don't. The Food Safety and Standards Authority of India (FSSAI) guidelines do not mandate testing milk for cortisol, and most labs do not have the requisite infrastructure to conduct these tests. India does not even have guidelines specifying the maximum safe limit of the hormone in dairy products, unlike countries like Japan.

The only way to ensure that dairy animals are being treated well, is to become conscious of our consumption

The solution, within the existing landscape, is to try and ascertain how cattle are treated in dairy farms. Some responses of cattle to their environment or management are natural, and any milk we consume will have traces of cortisol. While cortisol acts as a litmus test to confirm or deny stress, looking out for good management practices, like not tethering livestock, emerges as a key indicator of well-being.

The only way to ensure that dairy animals are being treated well, is to become conscious of our consumption. But better decisions cannot come from a system that does not make information public and accessible. Conscious consumption can only come after traceability, and the capacity to trace which livestock systems one’s dairy is coming from.

Also read: Keeping it cool: How to spot signs of heat stress in buffaloes