Are you reaching for another cup of steaming coffee, hoping for a hot, caffeine-induced energy boost in the middle of this dreary, cold winter weather? You’re not the only one. Caffeine is the most widely used psycho-active substance in the world.

Globally, 76 mgs of caffeine/person is consumed each day. In North America our intake is much higher – averaging 238 mgs/person every day.

The line at your local coffee shop will show that North Americans love their coffee, making the coffee “bean” the world’s primary source of caffeine. Although most 8-oz. servings of traditional coffee contain around 100 mgs of caffeine and most 2-oz. servings of espresso contain 100 mgs, the actual caffeine amounts vary according to the coffee bean used for the brew. Caffeine density depends on the species of the coffee bean plant; the way the beans were roasted and the way the coffee was prepared. In general, the darker the roast of the bean, the less caffeine in the coffee since the roasting process reduces caffeine content.

If you don’t prefer coffee, try tea for your caffeine boost.

Tea comes in hundreds of tasty varieties: black, white, green, oolong, and yerba mate; each variety’s caffeine levels vary, depending on the amount of oxidation that occurs in the leaf after it is picked – more oxidation creates higher caffeine levels. Black tea has the most oxidation and white tea has the least. Accordingly, an 8-oz. cup of black tea can deliver 40-72 mgs of caffeine, while white tea offers between 25-55 mgs, depending on the region in which it was grown.

Alternatively, you may drink pop, which often contains a significant amount of caffeine. Kola nuts, a natural source of caffeine with up to 25 mgs/gram, were initially Coca-Cola’s only source of caffeine. Currently, most soft drinks with caffeine use purified caffeine as the sole source instead. Sports/energy drinks are loaded with caffeine: Red Bull – 80 mgs/8.5-oz.; Coca-Cola – 23 mgs/8-oz.; Pepsi One – 36 mgs/8-oz.; and Mountain Dew – 36 mgs/8-oz.

Or, perhaps, you’d rather eat your caffeine in chocolate. Chocolate’s caffeine comes from the seeds of the cacao plant.

However, one bar may not give you the boost you want, since cacao seeds only offer a small amount – just 2.5 mgs/g. A typical, 28-gram milk chocolate bar only has about 20 mgs of caffeine – a good excuse for eating two.

No matter the source, your body quickly absorbs any caffeine you ingest. Within 15-120 minutes you feel caffeine’s effects; these effects wear off within five hours.

By stimulating your nervous system, caffeine can help fight off fatigue and to improve alertness, concentration and focus. Most healthy adults can enjoy moderate doses of caffeine, 200 to 300 mgs/day, without any bad effects. Regular, moderate coffee consumption may actually improve your health, according to the findings of an 18-year study conducted by Harvard University.

The study found that people who drink one to three cups of coffee each day significantly reduced their risk of developing: Parkinson’s disease – by 80%; cirrhosis of the liver – by 80%; gallstones – by 50%; colon cancer – by 20%; and diabetes – by at least 9%.

So, two to four cups of brewed coffee a day should be fine for your health unless you have sensitivity to caffeine or you have sleep pattern problems due to other factors, such as: travel, stress, work, etc.

In contrast, higher caffeine intake – 500 to 600 mgs/day, can affect your health quite negatively, causing insomnia, nervousness, dizziness, restlessness, irritability, upset stomach, dehydration, rapid heartbeat and/or muscle tremors. Caution: extremely high intake can be fatal.

Also, be aware that medications and/or herbal supplements, particularly antibiotics can impact the way your body processes caffeine. Cipro (ciprofloxacin) and Noroxin (norfloacin prolong caffeine’s effects by increasing the length of time caffeine remains in your system. Since theophelline (Theo-24, Elixophyllin), a drug used to open up the bronchial airways, mimics caffeine’s effects, it exacerbates caffeine’s effect on your system. Theophelline, if taken with caffeine, may cause nausea, vomiting, and/or heart palpitations. Echinacea, an herbal supplement used to prevent infections, may also increase the concentration of caffeine in your blood.

Considering all these factors, you may want to examine your caffeine consumption. If you feel you should cut back, reduce your intake slowly to avoid the caffeine withdrawal symptoms of headaches, fatigue, irritability and nervousness.

Start by consciously monitoring your actual caffeine intake. Reduce your intake by ordering fewer caffeine drinks, choosing smaller portion sizes, or switching to a decaffeinated alternative.

Shorten your brewing time for regular tea, or try a caffeine-free herbal tea. Read all labels. Over-the-counter pain relievers often contain as much of 130 mgs of caffeine per dose.

Caffeine is best when used in moderation. Certainly, caffeine can deliver an occasional boost to jump-start your day and/or recharge your batteries, but healthy foods deliver your body’s best fuel.