Caffeine scene – what’s the right amount for good health? with guest expert Denise Leyden APDExpert Examiner, Nutrition News — By Emma Stirling on March 4, 2011 at 10:33 am
Caffeine is a staple in many of our lives. It’s what wakes us up and often allows us to keep up with our busy day. Plus where would many of us be without that break we get from a coffee catch up or pop out? Whether caffeine is good or bad for our health is something that has been debated for many years. Let’s see if you are on track with the latest guidelines.
Denise is a recent graduate dietitian with a Bachelor of Health Science in Nutrition & Dietetics. She has a mild obsession with collecting cookbooks and gets excited when talking about food and health and can’t wait to start her career. Check out her healthy tweets.
What’s the right amount?
Caffeine is a natural substance found in some plants including coffee, cocoa beans, tea bush and guarana berries. Caffeine can be found in everyday foods including coffee, tea, iced tea, chocolate and of course energy drinks. As a stimulant caffeine acts on the brain and central nervous system, which is why it can make us feel more awake and perks us up. Caffeine and its effects can last up to 6 hours after consumption, however the amounts found in everyday day foods will vary considerably – here’s a general guide of caffeine content in common foods.
|Tea||150 ml||30–100 mg|
|Cocoa||150 ml||30–60 mg|
|Cola or Diet Cola soft drink||250 ml||35 mg|
|Chocolate milk drink||250 ml||2–7 mg|
|Energy drink||250 ml||80 mg|
|Milk chocolate bar||55 g||3–20 mg|
|Dark chocolate bar||55 g||40–50 mg|
Adapted from DrugInfo.
A low dose of caffeine is classified as being between 80mg-250mg of caffeine per day for adults, or the equivalent of 1-3 cups of instant coffee per day. Caffeine doses within this range have been associated with increases in alertness, mood, efficiency and concentration. However even at this low dose, caffeine has been shown to interfere with quality of sleep in some individuals, especially if consumed in the late afternoon or evening.
Too much caffeine can induce side effects such as jitters, anxiety and cause your heart beat to accelerate. This may happen if you have a bumped up to a high intake, have increased your intake dramatically in the short-term or returned to caffeine after a period of caffeine-free days. A high dose of caffeine is considered to be more than 500mg caffeine per day for adults.
Caffeine is often referred to as a legal drug and is used as a sports performance or “ergogenic” aid where caffeine pills and supplements are commonly used (and abused). The Australian Institute of Sport has an excellent fact sheet on caffeine. Caffeine is addictive and is able to induce withdrawal symptoms if you go cold turkey. Added into this cycle is the fact that your body builds a tolerance to caffeine after a while, meaning that sometimes we may find ourselves needing more caffeine than usual to get the same effect.
Are we drinking too much?
FSANZ (Food Standards Australia and New Zealand) conducted a report on the safety of caffeine back in 2000 and found that the caffeine levels that are typically consumed in current diets may lead to physical dependence in adults and withdrawal symptoms such as an increase in irritability, headaches and tiredness when ceased. But how has caffeine intake changed in the last ten years with the surge of energy drinks on the market?
There is evidence to suggest that some people are caffeine-sensitive and therefore caffeine has a greater effect on these people, but generally speaking low doses of caffeine have been shown to be safe for adults and can provide positive outcomes such as improved mood and productivity. You need to watch out with:
Pregnancy – caffeine has the ability to cross the placenta and may cause harm to the foetus when consumed in large amounts, including an increased risk of miscarriage and low birth weight. The current recommendations on caffeine consumption during pregnancy are a limit of 200mg caffeine per day, equivalent to around 2-3 cups of coffee. It’s wise to limit your consumption and many pregnant and breastfeeding women choose to avoid caffeine altogether.
Osteoporosis risk – caffeine intake has been associated with increased calcium loss which in turn may lead to bone mass loss and consequently osteoporosis. Therefore if you consume caffeine on a regular basis in large amounts, be sure to have an adequate intake of calcium and monitor your levels on a regular basis. Speak to your health professional if you have a family history of osteoporosis.
Children & teens – currently there are no recommendations for safe level of caffeine in children as there is limited information around both the short term and long term effects of caffeine on children, especially on brain development. FSANZ have reported that there may be an increase in anxiousness in children following a caffeine dose of 95mg per day.
Wow, that’s refreshing
There is new news about caffeine and hydration, which is still catching on with health professionals too. Until recent times it was accepted that caffeine was “dehydrating” or had a “diuretic” effect that made you run for a bathroom break. Recent research has found that caffeine is not dehydrating as long as you are a regular, otherwise known as habitual drinker. You see, your body is able to adapt to ensure that it is running as best as it can and retains the fluid in caffeine-containing drinks. The (US) Institute of Medicine has concluded that caffeinated beverages can contribute to your fluid needs as discussed in this (beverage industry supported) interview with Dr Ann Grandjean on the caffeine-hydration myth:
The expert panel…..reviewed the existing scientific literature related to caffeine and hydration, including a number of newer studies published within the past decade. They determined there was sufficient scientific evidence finding that caffeine-containing beverages do not increase 24-hour urine volume in healthy individuals compared to other beverages and that caffeinated beverages appear to contribute to the body’s daily total water intake in amounts similar to that contributed by non-caffeinated beverages.
If you are not a regular consumer of caffeine or have taken a break from caffeine, you may experience a dehydrating effect once you go for it again.
Thanks Denise, that’s a very interesting update. I’m definitely one of those people that can’t drink coffee after 4pm. But my hubby is a double shot dude from morning to night. How about you lovely readers? How many cups a day do you down? What’s your top coffee pick? Love to hear your comments below.