From Tree to Table: What You Should Know About Birch Sap

Birch sap flows from trees across northern Europe, North America, and parts of Asia, where cold winters and temperate springs allow safe harvesting. Each year, between February and early April, there is a 3–4 week window for collecting it.

Harvesting highly depends on location and temperature changes. When daytime temperatures rise above 50°F (10°C), and nighttime temperatures still fall below freezing, it is time to collect birch sap.

This seasonal drink is still finding its place in the market, but is gaining attention in the cosmetics industry. That caught our attention, so we decided to examine the benefits of birch sap, its use, and sustainability.

Birch sap comparison to other natural drinks

Maple water is probably the most famous sap, mainly because maple syrup is made from it. It is known to be rich in nutrients and may have antioxidant and anti-inflammatory activities.

The second natural drink that comes to mind is coconut water. Besides its hydrating properties, it is also rich in minerals and vitamins, which may contribute to various biological activities, similar to maple water.

In this competition, birch sap sometimes gets overlooked because of its short harvesting season and limited awareness. That said, let’s look at the nutrition profiles of each drink to see birch sap’s potential. See the table below for details.

“Birch sap has a light texture and flavor profile which is less than that of coconut water or maple water, yet still has a unique character all its own,” says Dr․ Sarah Boss, a Clinical Director at The Balance Rehab Clinic, on why she drinks birch sap.

She notes that the drink is easily digestible and won’t irritate your stomach. “It is a soft reset for the body,” she describes.

Rich in manganese

As shown in the table above, birch water stands out for its high manganese levels. This mineral may support bones, immune function, and aid wound healing. It also helps protect cells from damage and supports normal growth and reproduction.

The risks from excessive manganese consumption

The recommended daily intake of manganese for adults is 2.3 mg for men and 1.8 mg for women. Birch sap (10 oz) can contain up to 3 mg of manganese. Does this mean you will get intoxicated? Generally speaking, no. Toxicity is most often seen in medical situations, such as parenteral nutrition or industrial exposures.

For healthy individuals, manganese from foods and beverages is usually safe because the gut limits absorption and removes excess. Moderate consumption of birch sap is considered safe.

However, regularly drinking very large amounts could increase manganese exposure, especially in people with liver problems who may not efficiently eliminate excess manganese.

Allergic reaction

Dr. Boss warns that the drink contains birch. “For some people, birch is an allergen or sensitizer, meaning that it can cause an allergic-type reaction,” she continues.

Some researchers have investigated birch sap as a way to treat allergies, but this hasn’t led to major findings. If you are sensitive to birch pollen, consider skipping this drink and trying coconut water instead.

Use in cosmetics

Demand for natural ingredients in the cosmetic industry increases every year. Companies are looking for new ingredients to catch consumers' attention. Birch sap became popular in Korean cosmetics a few years ago and now appears in moisturizing creams, sheet masks, toners, mists, and more.

It is known for hydration, antioxidant effects, and supporting sensitive skin, at least according to cosmetic companies. But is there supporting evidence? Let’s take a look.

A small clinical study evaluated the effects of birch sap-based spray on 33 individuals with sensitive skin over 28 days. Their results were compared to a control group. Researchers noticed that participants using the birch sap spray improved skin barrier function, including reduced transepidermal water loss (TEWL) and increased stratum corneum (SC) hydration.

Lowering TEWL prevents dehydration and premature aging, while increased SC hydration enhances skin barrier function and improves elasticity. They also experienced less redness and irritation.

Even though it shows potential benefits, more research on humans is needed. For example, a 2024 study explored white birch sap as a natural alternative to traditional skin-whitening agents, as these agents can cause side effects such as irritation and toxicity.

Birch sap was found to contain bioactive compounds with antioxidant properties that may help regulate skin pigmentation. However, the study was conducted in zebrafish, so it is hard to predict whether it will have the same effect in humans.

Dr. Boss says birch sap may hydrate and soothe your skin, but it will not deliver fast results or replace your daily skincare routine. “Healthy looking skin is created through daily care and with the right ingredients,” she sums up. Still, birch sap may show more potential in the future, and we should keep an eye on it.

Fresh or bottled birch sap?

Raw birch sap can be delicious, as it's cold, fresh, and has a bit of sweetness. However, it contains naturally occurring bacteria. Microbial levels tend to be higher at the end of the tapping season and lower at the beginning.

Consuming raw birch sap without proper processing could cause gut issues, especially if microbes multiply. For this reason, it is best to consume store-bought sap, as it has undergone cleaning.

If you are still interested in drinking birch sap straight from a tree, do so earlier in the season. Decided to bottle it up? Fresh sap can ferment quickly and change over just a few days if kept at warmer or room temperature. Keep it in the fridge and boil it before then to reduce the microbial load.

If you think you can freeze it instead of boiling it, think twice. Research shows that freezing only reduces but does not eliminate microbes.

Final word

Nothing can replace water for hydration; that is the fact. However, once a year, when it is the season, birch sap can be a delicious drink that satisfies your sweet cravings. It is low in sugar and serves a better purpose than a can of soda, as it has some minerals and vitamins.

That said, keep in mind that 10 oz serves more manganese than the recommended daily value. Even though you are not likely to overdose on this mineral, responsible consumption is advised.