Seabuckthorn Leaves: from Himalayan Research to your Teacup

The brilliant orange berries of seabuckthorn get most of the attention. But what about the leaves? From research inspired by life in the Himalayas to studies of what actually enters a cup of tea, these slender leaves have a remarkable story of their own.

Walk through our Saskatchewan seabuckthorn orchard in summer and you'll see branches covered with silvery-green leaves. Later, many of those branches will carry clusters of brilliant orange berries.

At Northern Vigor Berries, we have grown seabuckthorn since the late 1990s. We've long appreciated the berries, but we've also come to value the leaves, which we harvest in June for our nvigorate organic whole-leaf seabuckthorn tea.

Scientists around the world have been asking questions about these leaves. What natural compounds do they contain? Why did Indian defence researchers investigate them for extreme environmental stress? And perhaps most relevant to tea drinkers: do any of those compounds actually enter the water when the leaves are brewed?

FROM THE HIMALAYAS: WHY INDIAN DEFENCE SCIENTISTS STUDIED SEABUCKTHORN LEAVES

Imagine working high in the Himalayan mountains, where severe cold and low oxygen place extraordinary demands on the body. Those conditions helped inspire scientists at India's Defence Research and Development Organisation (DRDO) to investigate plants that might influence physiological responses to environmental stress.

Researchers at the Defence Institute of Physiology and Allied Sciences (DIPAS) studied extracts made from seabuckthorn leaves. In a 2007 study published in Food and Chemical Toxicology, laboratory rats received a water-based leaf extract before being exposed to a combination of cold, reduced oxygen and restraint stress. The researchers reported improvements in experimental measures of stress tolerance.

Additional studies explored oxidative-stress markers, metabolism and responses to low-oxygen conditions. In 2015, researchers compared several seabuckthorn varieties and found that the effects of their leaf extracts differed.

India's defence research organizations also developed seabuckthorn-based products, including a multi-herb tea formulation. An Indian Ministry of Defence announcement in 2015 described a technology-transfer agreement involving several seabuckthorn products, including that tea.

WHAT DID THOSE EXPERIMENTS ACTUALLY SHOW?

The research is fascinating, but the distinction matters: these were mainly animal experiments using prepared extracts, not clinical trials proving that soldiers who drank ordinary seabuckthorn leaf tea experienced less stress or better altitude tolerance. The multi-herb tea also contained other plants, so its properties cannot be credited to seabuckthorn alone.

Some of the experimental extracts were water-based, making the findings especially interesting to tea researchers. Even so, a concentrated extract is not equivalent to a cup brewed with a couple of leaves.

WHAT MAKES SEABUCKTHORN LEAVES INTERESTING?

Much of the scientific interest centres on naturally occurring plant compounds known as polyphenols. These substances occur in many fruits, vegetables, herbs and teas.

Seabuckthorn leaves contain several groups of compounds that have attracted researchers' attention:

• Flavonoids, including compounds related to quercetin, isorhamnetin and kaempferol

• Ellagitannins, including compounds such as stachyurin and casuarinin

• Phenolic acids, a diverse group of naturally occurring plant substances

• Polysaccharides, complex carbohydrates studied in laboratory experiments

Researchers have measured antioxidant activity in laboratory tests involving seabuckthorn leaf preparations. They have also investigated leaf extracts in experiments involving inflammation, metabolism and immune-cell responses.

Antioxidant activity in a laboratory test, however, is not proof that drinking the tea produces a particular health benefit in people. The human evidence remains limited.

DO THESE COMPOUNDS ACTUALLY ENTER THE TEA?

This is an especially important question for those of us who enjoy seabuckthorn as a beverage. Finding a compound inside a leaf is one thing; showing that it moves into hot water is another.

RESEARCH ON BREWED TEA

A 2019 study published in Food Chemistry identified flavonoids and ellagitannins in seabuckthorn leaf infusions. The researchers also found that the seabuckthorn variety and the way the leaves were processed influenced the tea's chemical composition.

A 2023 study published in Phyton examined fresh and dried leaves prepared with hot water. One experimental preparation steeped approximately 2 grams of leaves in 200 millilitres of water for 10 minutes. The researchers found that steeping extracted several polyphenols more effectively than simply passing water through the leaves.

The important finding is that some of the naturally occurring compounds in seabuckthorn leaves do pass into the brewed tea. The exact amounts depend on the variety, processing, quantity of leaves, temperature and brewing time.

The 2-gram quantity used in research was an experimental method, not our suggested serving. For our own whole-leaf tea, we generally recommend starting with just a couple of large leaves per cup.

WHAT HAVE OTHER COUNTRIES DISCOVERED?

Researchers in China have investigated seabuckthorn leaves prepared using different tea-processing methods. A 2022 study in Frontiers in Nutrition reported that processing influenced both the compounds identified and the results of laboratory antioxidant tests.

Other researchers have compared commercial seabuckthorn leaf teas, finding differences in flavour, polyphenols and antioxidant measurements. Still others have examined isolated leaf compounds and concentrated extracts in laboratory or animal models involving metabolism, inflammation and intestinal health.

These studies open interesting areas for future work, but they do not establish that drinking ordinary seabuckthorn leaf tea prevents illness, boosts immunity or treats medical conditions.

A comprehensive scientific review published in 2026 likewise emphasized the need for controlled human research on well-characterized seabuckthorn leaf preparations.

SEABUCKTHORN LEAVES AND BERRIES: TWO DIFFERENT STORIES

Our brilliant orange berries are known for their tart flavour and naturally occurring vitamin C, carotenoids and oils. The leaves have a different chemical profile, with particular scientific interest in their flavonoids, ellagitannins and other polyphenols.

Some studies have found higher concentrations of certain phenolic compounds in the leaves than in the berries. That does not mean one is necessarily better than the other. They are different parts of an extraordinary plant, each with its own characteristics.

It also does not mean that a brewed cup contains everything found in the whole leaf. What ends up in the water is influenced by the preparation.

A NATURALLY CAFFEINE-FREE ALTERNATIVE TO GREEN TEA

Traditional green and black teas come from Camellia sinensis, the tea plant, which naturally contains caffeine. Seabuckthorn leaf tea is made from a different plant and is naturally caffeine-free.

For customers who enjoy a warm herbal beverage but prefer to avoid caffeine, this can be an appealing choice at different times of day.

Some of our customers have made the tea part of their family's routine. However, caffeine-free does not automatically mean that regular use has been established as safe for children of every age. Research specifically examining seabuckthorn leaf tea in young children is limited.

DOES WATER TEMPERATURE MAKE A DIFFERENCE?

Water temperature influences how plant compounds are extracted. Some compounds are more heat-sensitive, while others are released more effectively as the water becomes hotter.

A 2022 brewing study reported that approximately 80°C (176°F) with a six-minute infusion gave the best result for the laboratory antioxidant measurement used in that experiment. Other research has successfully extracted leaf polyphenols using boiling water and longer steeping times.

These findings do not establish one universally perfect temperature or show that boiling water destroys all the leaves' antioxidants. They also measure chemical activity in the infusion, not a demonstrated health effect in a person.

There is a separate food-safety consideration: authorities such as Germany's Federal Institute for Risk Assessment recommend preparing dried herbal infusions with freshly boiling water and steeping for at least five minutes because dried plant material may contain microorganisms. For home preparation, food safety should take priority over trying to maximize a laboratory antioxidant score.

HOW WE ENJOY OUR WHOLE-LEAF TEA AT NVIGORATE

After years of growing seabuckthorn and introducing customers to our tea, we've developed a simple approach to preparing it.

1. Start with a couple of large dried seabuckthorn leaves per cup.

2. Add freshly boiling water and let the leaves steep for at least five minutes.

3. Adjust the quantity of leaves and steeping time to suit your taste.

4. Enjoy it warm, or cool it promptly and refrigerate it for an iced herbal tea.

Unlike seabuckthorn berries, which have a vivid tart, citrusy flavour, the leaves produce a gentler herbal drink.

ONE THING WE'VE NOTICED ABOUT LONG STEEPING

There's something we particularly enjoy about our seabuckthorn leaves: in our experience, they don't develop the pronounced bitterness that some traditional teas can acquire when left to steep for a long time.

We have often kept our tea in a heated urn, leaving the leaves immersed in the hot water throughout the day. The flavour becomes a little stronger, but we've found that it remains pleasant rather than turning sharply bitter.

That is our own experience with our leaves, not a scientific claim about every seabuckthorn tea. If using a heated urn, it is important to follow safe hot-holding practices rather than allowing the beverage to sit lukewarm for hours.

For variety, a little lemon, honey or seabuckthorn berry purée can offer a different flavour experience.

FROM OUR SASKATCHEWAN ORCHARD TO YOUR TEACUP

We planted our first seabuckthorn orchard in Saskatchewan in the late 1990s. Since then, this hardy plant has become a familiar part of our family farm.

It withstands our prairie winters and grows through long summer days. We harvest the leaves in June, well before our late-summer berry harvest, and prepare them as nvigorate organic whole-leaf seabuckthorn tea.

We love that the dried leaves retain their recognizable long, narrow shape. And we find it remarkable that the same kind of leaves we gather in our prairie orchard have interested researchers working on questions as varied as tea chemistry and survival under extreme Himalayan conditions.

A SUMMARY:  A LITTLE LEAF WITH A REMARKABLE STORY

Seabuckthorn leaves may never be as colourful as the berries, but they deserve attention of their own.

Scientists have identified many naturally occurring compounds in the leaves and confirmed that some of them pass into hot water when the tea is brewed. The Indian defence research adds a fascinating chapter to that story, while the more recent tea studies tell us about the drink itself.

Much remains to be learned about health effects in people. But for us, the research makes a simple cup of seabuckthorn leaf tea all the more interesting.

Sometimes nature's most intriguing discoveries are found in the parts we might otherwise overlook.

Discover nvigorate Organic Seabuckthorn Tea Leaves, grown on the Canadian Prairies and harvested with care.

nvigorate — Canadian Superfruit Nutrition

SCIENTIFIC REFERENCES

1. Saggu, S., et al. (2007). Adaptogenic and safety evaluation of seabuckthorn (Hippophae rhamnoides) leaf extract: A dose dependent study. Food and Chemical Toxicology. Research.

2. Saggu, S. & Kumar, R. (2007). Possible mechanism of adaptogenic activity of seabuckthorn during exposure to cold, hypoxia and restraint stress. Food and Chemical Toxicology. Research.

3. Sharma, et al. (2015). In vitro antioxidant profiling of seabuckthorn varieties and their adaptogenic response to high altitude-induced stress. International Journal of Biometeorology. Research.

4. Ma, X., et al. (2019). Phenolic compounds and antioxidant activities of tea-type infusions processed from sea buckthorn leaves. Food Chemistry. Research.

5. Wang, N., et al. (2022). Identification and characterization of the bioactive polyphenols and volatile compounds in sea buckthorn leaves tea. Frontiers in Nutrition. Research.

6. Zhu, Y., Ran, L. & Zhou, H. (2022). To optimize the brewing process of leaf tea from Hippophae rhamnoides Linn by the antioxidant activity and to explore its anticoagulant activity. American Journal of Biochemistry and Biotechnology. Research.

7. Raal, A., et al. (2023). Polyphenolic compounds and antioxidant activity of sea buckthorn. Phyton. Research.

8. He, et al. (2023). Phenolic compounds, antioxidant activity and sensory evaluation of sea buckthorn leaf tea. Food Science & Nutrition. Research.

9. Kordas, A. & Majewski, M. S. (2026). Sea Buckthorn in Cardiovascular and Metabolic Health: Evidence for the Role of the Leaves. Nutrients. Review.

10. Government of India, Ministry of Defence (2015). DRDO collaboration involving seabuckthorn-based products. Announcement.

Research note: Studies of isolated compounds, animal models and concentrated extracts should not be interpreted as proof that drinking seabuckthorn leaf tea prevents or treats illness.