Is There Calcium in Lime Water? Demystifying the Chemistry

November 28, 2025 •

3 min read

While most people associate "lime water" with a citrus-infused drink, a saturated solution of calcium hydroxide is also referred to by this name. This critical distinction is the key to understanding if there is calcium in lime water, as the mineral-based version contains calcium while the fruit-based version contains very little.

Quick Summary

This article clarifies the difference between calcium hydroxide-based limewater and citrus fruit-infused water, detailing their respective calcium content. It explains how limewater, made from slaked lime, contains calcium, while the refreshing citrus drink has minimal amounts. The article explores the chemical makeup and practical applications of both preparations.

Key Points

Two Meanings: The term "lime water" refers to two very different liquids: a chemical solution of calcium hydroxide and a beverage made with citrus fruit.
Limewater Contains Calcium: The chemical solution known as limewater contains calcium in the form of dissolved calcium hydroxide ($Ca(OH)_2$).
Citrus Water Has Minimal Calcium: Water infused with citrus lime juice contains only a very small, nutritionally insignificant amount of calcium.
Caustic vs. Edible: Chemical limewater is caustic and unsafe for consumption, while citrus lime water is a safe and healthy beverage.
Identify by Purpose: The easiest way to tell the difference is by its use: industrial and lab applications use calcium hydroxide, while beverages use citrus fruit juice.
Benefits of Citrus Lime Water: The health benefits of drinking citrus lime water primarily come from vitamin C and antioxidants, not its trace calcium content.

The phrase "lime water" can be confusing, as it refers to two completely different substances. One is a chemical solution used in scientific and industrial applications, and the other is a common beverage made with citrus fruit. The presence and type of calcium depend entirely on which version is being discussed. This article will clarify the distinction and provide a comprehensive overview of the chemical makeup of both.

The Chemical Distinction: Limewater vs. Citrus Water

To understand the calcium content, it is essential to define the two types of 'lime water.' Limewater (one word) is a scientific term for a saturated solution of calcium hydroxide ($Ca(OH)_2$), also known as slaked lime. This is an alkaline, inorganic compound produced by mixing calcium oxide with water. It is a key ingredient in many chemical processes and industrial applications.

Conversely, 'lime water' (two words) often refers to a beverage made by squeezing juice from a citrus lime fruit into water. This is a popular drink enjoyed for its refreshing flavor and vitamin content. The source of the 'lime' is the defining factor, with one being a mineral compound and the other a fruit.

Calcium Hydroxide (Limewater)

Limewater is, by definition, a solution containing calcium. Specifically, it is calcium hydroxide dissolved in water. While calcium hydroxide is only sparsely soluble in water, the portion that does dissolve forms a basic solution with a pH of around 12.4. The dissolved calcium ions are readily available in this solution, making it a source of calcium for specific applications, such as marine reef aquariums. However, this form of limewater is caustic and should not be consumed by humans.

Citrus Lime Water

Water infused with citrus lime juice contains trace amounts of calcium, but it is not a significant source. The primary health benefits of this beverage come from its high concentration of vitamin C and antioxidants. A typical lime contains only about 22 milligrams of calcium, a minimal amount compared to daily nutritional requirements. Drinking citrus lime water contributes to hydration and provides vitamins, but it is not a reliable or meaningful source of calcium for your diet.

Comparison Table: Limewater vs. Citrus Lime Water


Feature	Limewater (Calcium Hydroxide)	Citrus Lime Water (Fruit Juice)
Primary 'Lime' Source	Calcium-rich mineral compound (limestone)	Citrus fruit (e.g., Persian or Key lime)
Chemical Formula	$Ca(OH)_2$ in a saturated aqueous solution	Mixture of water, citric acid, and vitamins
Calcium Content	High (contains dissolved calcium ions)	Very low (negligible from a nutritional perspective)
Taste Profile	Bitter/astringent and alkaline	Tart, acidic, and refreshing
pH Level	High (around 12.4), strongly alkaline	Low (acidic)
Safe for Human Consumption?	No, it is caustic and harmful	Yes, and it offers health benefits from vitamin C
Common Uses	Industrial applications, reef aquariums, lab tests	Hydration, flavor enhancement, cooking

Practical Applications of Limewater (Calcium Hydroxide)

Limewater, the calcium hydroxide solution, has several practical uses that demonstrate its high calcium content:

Reef Aquariums: Marine aquarists use limewater, often called Kalkwasser, to supplement calcium and alkalinity levels necessary for corals to grow their skeletons.
Carbon Dioxide Test: In chemistry labs, limewater is used to detect the presence of carbon dioxide ($CO_2$). When $CO_2$ is bubbled through the solution, it reacts with the calcium hydroxide to form insoluble calcium carbonate ($CaCO_3$), which precipitates out and makes the solution cloudy or milky.
Food Processing: Limewater has been used in some traditional food preparation techniques, such as for soaking corn (nixtamalization) or in preparing certain sweets, to improve texture and nutritional value.
Wastewater Treatment: Industrially, calcium hydroxide is used as a neutralizing agent in the treatment of municipal wastewater.

Conclusion

To answer the question "is there calcium in lime water?" requires a crucial clarification. The scientific term 'limewater,' a saturated solution of calcium hydroxide, is indeed rich in dissolved calcium. This substance is caustic and used for industrial purposes. The beverage 'lime water,' made from citrus fruit, contains only trace amounts of calcium. The calcium you get from the fruit-infused drink is negligible from a dietary perspective. For most people, consuming water with citrus lime offers valuable vitamin C and hydration, but not a significant source of calcium. Understanding the difference between these two definitions prevents confusion and ensures proper use of each substance.

For more information on the chemical properties of calcium hydroxide, you can visit the Wikipedia page on Calcium Hydroxide.

Frequently Asked Questions

No, the calcium content in citrus lime fruit is very low. A single lime contains only about 22 milligrams of calcium, which is a minimal contribution to your daily nutritional requirements.

No, you must never drink chemical limewater (calcium hydroxide solution). It is a caustic substance that can cause chemical burns if ingested. For dietary calcium, you should rely on foods or supplements recommended by a healthcare professional.

The key chemical difference is the primary ingredient. Chemical limewater is a solution of calcium hydroxide ($Ca(OH)_2$), a mineral compound. Citrus lime water is an aqueous solution of citric acid and other compounds from the fruit.

You can test for carbon dioxide by bubbling the gas through a limewater solution. The solution will turn milky or cloudy as the $CO_2$ reacts with calcium hydroxide to form insoluble calcium carbonate.

Marine aquarists use limewater (often called Kalkwasser) to replenish calcium and alkalinity in the water. These are crucial elements for hard corals and other organisms to build their calcium carbonate skeletons.

A person with a calcium deficiency will not benefit significantly from drinking citrus lime water due to its very low calcium content. They should focus on other, more effective dietary sources or supplements.

The health benefits of drinking water with citrus lime include improved hydration, an intake of vitamin C and antioxidants, and potential benefits for skin health, immunity, and digestion.