Holly Spindler
Factory farming has forced modern chickens have ballooned in size compared to their ancestors, but what is causing this fast growth?
Chickens raised for meat, also known as broiler chickens, grow 400% faster than they did 50 years ago, in order to reach market weight in 60% less time.
But while you might assume that modern chickens are given hormones in order to reach this size—this isn’t actually the case.
Are chickens injected with something to make them grow?
In the UK, it has been illegal for chicken producers to use antibiotics as growth-promoters since 2006. While antibiotics are given to chickens through their feed or water, in the UK this is only done to help prevent disease in the filthy, overcrowded conditions.
The larger size of today’s broiler chickens is due to selective breeding over generations. This has resulted in breeds of chicken that have suffering coded into their DNA. We call them “Frankenchickens”, and their size and fast growth can mean chickens suffer a variety of health problems.
How does rapid growth affect chickens?
Just because growth enhancers aren’t used on chickens in the UK, this doesn't mean there is anything natural about how quickly and how large chickens are bred to grow.
Modern day factory farmed chickens originated from the junglefowl. But industrial farming has used selective breeding to force chickens to grow so big, so quickly, that they reach slaughter weight in just a few weeks.
Their bodies often cannot cope with such excess weight and can result in chickens being unable to walk. This can leave some birds laying in their own waste, causing painful burns to their delicate skin. They also may suffer from a range of other health problems, including organ failure and difficulty breathing.
Are hormones or steroids given to chickens outside the UK?
In the UK, it’s illegal to use hormones or steroids to promote growth in any farm animal, including chickens.
However, this isn’t the case elsewhere and there are ongoing concerns, especially following Brexit, that new trade deals will open the UK up to imports of this meat.
Does chicken contain natural hormones?
Given the strict regulations in the UK and other countries, chicken shouldn’t contain unusually high levels of hormones. However, all animals—humans included—naturally produce their own hormones like estrogen, progesterone, and testosterone.
This means chicken meat naturally contains some level of these hormones.
Do hormones in chicken affect humans?
Not much is known about how naturally-occurring hormones in chicken affect the humans who consume them. However, one study notes that the amount of chicken eggs and meat consumed in the Western diet increases levels of the hormone estradiol in the body. The study notes: “High serum concentrations of free estradiol and testosterone have been associated with an increased risk of breast cancer in postmenopausal women and other diseases such as cardiovascular disease, increased triglyceride concentrations and insulin resistance.”
The bottom line
While the use of growth hormones and steroids is prohibited in UK chicken farming, sadly this doesn’t mean that farming practices are natural, or that they don’t cause immense levels of suffering to animals.
We’re working hard to end the use of fast-growing chicken breeds. Through our relentless campaigning, we’ve persuaded companies including KFC, Pizza Hut, and Waitrose to sign up to the Better Chicken Commitment (BCC), because chickens deserve better. If you'd like to join us, sign up to take action.
