What's the link between roast chicken and wrinkles?
My son's favourite dinner is without a doubt roast chicken legs. He asks for them every night but we compromise on having them once a week. You can therefore imagine that when I read that eating roast chicken could speed up the ageing process I had to investigate.
It turns out Advanced Glycation End Products (AGEs) are in part to blame.
AGEs are harmful compounds that are formed when protein or lipids combine with sugars. The formation of AGEs is a part of normal metabolism but they also exist naturally in food, especially animal derived products that are rich in protein and fat. Once the AGEs enter the bloodstream they basically wreak havoc on our cells. Yes our body has ways to eliminate these harmful compounds, including with antioxidants and enzymes. But the accumulation of AGEs have been shown to cause oxidative stress and inflammation, factors strongly linked with premature ageing and the development of many degenerative diseases such as Type 2 diabetes and Alzheimers (study and review).
Our modern western diet is a major source of AGEs. And its not just the type of food that contributes to dangerously high levels AGEs, its how we process it. Foods cooked at high temperatures (e.g. pasteurisation) and low moisture (e.g. grilling and roasting) or cheeses that are aged for example have much higher AGE content than their uncooked or unprocessed counterparts (see study). Processes used by food manufacturers to add flavour or colour to their products also boost AGE levels. In fact, dry heat promotes AGE formation by >10- to 100-fold above the uncooked state. Less AGEs are formed when food is steamed, poached, stewed, or boiled (methods that retain food moisture). Microwaving produces few AGEs because of its relatively short cooking times and cooking meat with acidic ingredients, such as vinegar or lemon juice can reduce AGE production by up to 50% (see study).
A comprehensive list detailing the AGE content of over 500 foods can be found here. As I mentioned earlier, much to my dismay roasted chicken legs feature a very high AGE count. As did one of my other favs, fried eggs. Overall foods highest in AGEs include meat (especially red meat), certain cheeses, fried eggs, butter, oils and nuts. Also fried foods and highly processed products contain high levels.
So think twice before you eat those chargrilled goodies as the more AGEs we eat the more we age on the inside!
The good news? There are a lot of things you can do to limit your intake of AGEs and therefore slow down the ageing process:
1. Marinating meat with acidic ingredients such as lemon juice or vinegar inhibits AGE formation. This is why I have been for years now roasting my chicken legs in apple cider vinegar. Tastes good too!
2. Modify cooking methods. Instead of frying your eggs, try poaching them etc. Slow cookers are considered one of the healthiest ways to cook meals. I can’t recommend getting one enough.
3. Limit foods high in AGEs. Diets rich in fruits, vegetables, whole grains, legumes and fish are low in AGEs. The Mediterranean diet is typically low in AGEs.
4. Eat a diet rich in Antioxidants. Natural antioxidants, such as vitamin C, quercetin and carnosine have been shown to hinder AGE formation in the laboratory. Animal studies have shown that some natural plant phenols such as resveratrol and curcumin can prevent the negative health effects of AGEs. Resveratrol can be found in the skins of dark fruits like grapes, blueberries and raspberries and curcumin is found in turmeric.
5. Cut out/down on sugar. Since sugar is a key ingredient in the Maillard reaction (the so-called browning of food and caramelisation), reducing it in the diet will lessen the chance of AGEs forming in the body. It is no surprise that diabetics who have elevated sugar levels are more prone to AGE-associated diseases. In a 1997 study, diabetic and healthy subjects were given a single meal of egg white, cooked with or without fructose; there was a greater than 200-fold increase in AGE immunoreactivity from the meal with fructose.
Are you going to make any changes to reduce your AGE load? Do you think AGEs will become the new marker of overall health?