Ask EN

September 2017 Issue




Akaline Water and Guarana Supplements

Q: Is alkaline water good for you?

A: Health advocates recommend drinking water as the best way to keep our bodies hydrated. At one time, turning on the tap was the way to satisfy a thirst, but nowadays there are scores of bottled waters for sale, many promising more than just hydration. Alkaline water is one among the many that line supermarket shelves.

The term “alkaline” is a measure of the pH of the water. The pH scale measures if a substance is acidic, basic (or alkaline) or neutral. Most water, bottled and tap, is close to neutral with a pH of 7. Alkaline waters have a pH above 8. While some spring waters are slightly alkaline, most of the bottled waters sold as “alkaline water” are produced through a process called ionization. The promised health benefits for alkaline waters include boosting metabolism, improving the absorption of nutrients, helping the body to “starve” cancer cells, and acting as an antioxidant. There is scant scientific support for any of these benefits of alkaline water. And people with poor kidney function should avoid alkaline water because the dissolved minerals in the water could harm the kidneys.

—Sharon Salomon, MS, RD

Q: Should I consume guarana ingredients or supplements?

A: Guarana is a plant native to South America, named for the Guarani Amazonian tribe who originally used the seeds in a bitter drink similar to coffee. Guarana was used as a stimulant by natives during times of fatigue and fasting. But recently it’s been added to drinks or used as a supplement to provide purported benefits.

The South American plant guarana

Diogo Piloto Proenca | Dreamstime.com

The South American plant guarana is rich in caffeine.

Researchers once believed the active ingredient of guarana was a chemical specific to the plant, but later discovered that it was actually caffeine, abundant in guarana. Caffeine has been found to have some benefits for mental alertness and physical performance. People take guarana with hopes that it will help increase performance and energy, improve mood, reduce anxiety, and promote weight loss. However, there is insufficient research to support these claims specific to guarana.

The potential side effects of guarana are similar to those of caffeine, including sleep problems, anxiety, restlessness, upset stomach, and quickened heartbeat. Long-term use of caffeine may result in tolerance and psychological dependence, and abrupt discontinuation can result in physical withdrawal symptoms including headache, irritation, nervousness, anxiety, and dizziness.

—Kaley Todd, MS, RDN