What Happpens to My Body... When I Drink Caffeine to Fill Me Up

By Dietitian, Juliette Kellow BSc RD

As well as curbing appetite, some of us believe that caffeine-containing drinks may help to boost our metabolism slightly. In reality though, the evidence for this is sketchy – increasing the amount of muscle we have through exercising regularly is likely to have a far greater impact on boosting our metabolism. Although drinking large amounts of diet cola and black coffee can help to fill us up without the calories, excessive amounts of caffeine may have some negative effects in the body.

• To start with, caffeine acts as a mild diuretic and so makes the body lose greater volumes of water than usual by increasing urine production. This means our need for fluid increases. As a result, the Food Standards Agency recommends that caffeinated drinks aren’t the only source of fluid in our diets.
• Excessive amounts of caffeine can also increase heart rate and lead to nausea and vomiting.
• Over time, caffeine is also known to reduce the amount of calcium in bones, increasing the risk of osteoporosis.
• Plus, as caffeine stimulates the central nervous system, too much can lead to restlessness, anxiety and jitteriness, and may disrupt sleep patterns, often making it harder for people who have consumed lots of caffeine during the day get to sleep. This in itself may make it even harder to shift those pounds as research consistently reveals a link between obesity and fewer hours of sleep.

WLR’s advice

Stick to around three cups of coffee a day. If you drink more than this, cut down gradually as sudden withdrawal can lead to symptoms such as headaches, irritability, nausea and drowsiness. In the meantime, replace some of the cola and coffee in your diet with sparkling water! The bubbles should help to fill you up.