Summer heat – does our body need more liquid now? Is it possible to drink too much? And is tap water better or worse than bottled water? Questions about drinking are answered by Prof. Dr. Diana Rubin, head of the Vivantes Center for Nutritional Medicine.
Prof. Dr. Rubin, is it true that water is best for the body?
Prof. Dr. Diana Rubin: Calorie-free drinks are definitely the best choice. As an alternative to water, you can also drink unsweetened tea or coffee.
How much fluid should be consumed per day in addition to food?
Rubin:Adults up to 65 years of age should consume approx. 1500 ml daily via beverages, i.e. 1.5 liters. Adults over 65 years about 1300 ml daily. About 700-900 ml should be added from food.
Do you have any recommendations especially for the summer?
Rubin: People who sweat a lot should drink at least 500 ml more per day. However, the feeling of thirst usually indicates the need in healthy people. However, this sensation can also be disturbed in older people. At the latest when headaches or muscle cramps occur, plenty should be drunk.
Are there negative effects if carbonic acid is contained in the water?
Rubin: No, the composition is not affected. However, carbonic acid causes bloating and flatulence in some people, and they may drink less as a result. Others, however, prefer to drink carbonated water and therefore find it easier to drink the recommended amount. The minerals are important.
When you say that minerals are important, what ingredients should people pay particular attention to?
Rubin: Mineral water contains very different amounts of minerals. You should look for a high calcium content and a low sodium content. Calcium is important for bone health and too much sodium can increase blood pressure.
Is bottled water healthier than water from the tap?
Rubin: No, you can't make that general statement. Bottled water is not recommended because of its low mineral content. However, Berlin tap water is certainly recommendable because it has a not inconsiderable mineral content. For example, it contains about 100 mg/l of calcium, which is more than in many mineral waters. However, there are also mineral waters with three to four times this amount.
However, drinking water distribution systems can also cause germ contamination, so it depends on the house distribution system whether tap water can be recommended without restrictions.
How long can people go without drinks or water?
Rubin: It varies from person to person, but about a week at most. The human body consists of 60 percent water and needs it for almost all life-sustaining processes.
What actually happens if you drink too much water?
Rubin: People with heart, kidney or liver problems in particular can store water in the body and should discuss the individually recommended drinking amount with their doctor. For healthy people, it is usually not harmful, even if the recommended drinking amount is significantly exceeded, because the water is quickly excreted through the urinary tract. In very rare cases, "water intoxication" can occur, but then the water must be drunk in large quantities over a very short period of time.
Should you always have something to drink with you when you are out and about, for example in the city?
Rubin: As a rule, this is not necessary. The body has a large water reservoir. However, if you are out and about for several hours and in high temperatures, it may be necessary to drink something in between.