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Hesperidin is one of the best-studied flavonoids in citrus fruit. Current research focuses on its relationship with markers of inflammation and oxidative balance.

What hesperidin is

Hesperidin is a natural plant compound belonging to the flavonoids, and more precisely to the flavanones. It is neither a vitamin nor a mineral, and no recommended daily intake has been established for it. In the plant it occurs as a glycoside: a hesperetin molecule is linked to a disaccharide made of glucose and rhamnose. The presence of the sugar moiety affects the compound's solubility and the way it is processed in the digestive tract.

Hesperidin dissolves poorly in water and is not absorbed in full in the small intestine. A significant part reaches the large intestine, where gut-bacteria enzymes detach the sugar moiety and release hesperetin. The compound can then be absorbed and converted mainly into glucuronide and sulfate derivatives. Differences in microbiota composition, the form of the preparation, particle size and meal composition can cause considerable inter-individual differences in availability.

Sources of hesperidin

Citrus fruits provide the most hesperidin, especially sweet and bitter oranges, mandarins, clementines and lemons. Its content depends on the species and variety, ripeness, growing and storage conditions, and processing. The compound is not evenly distributed — more is found in the peel, the white layer beneath it, the membranes separating segments and pressing residues than in the flesh itself.

Orange juice also contains hesperidin, but the amount can vary with the proportion of fine fruit particles, filtration and production technology. Supplements use, among others, purified, micronized or modified hesperidin to increase its solubility.

Inflammation and oxidative stress

Inflammation is a natural response to infection or tissue damage. In the short term it supports defence and repair, but when it persists too long it can proceed without clear symptoms. It is assessed using, among others, C-reactive protein (CRP), high-sensitivity CRP (hs-CRP), tumour necrosis factor alpha (TNF-α) and interleukin 6 (IL-6).

Oxidative stress arises when the body cannot keep up with neutralising reactive oxygen and nitrogen species. Their excess can lead to changes in lipids, proteins and DNA. Studies assess, among others, malondialdehyde (MDA), 8-hydroxy-2′-deoxyguanosine (8-OHdG) and total antioxidant capacity (TAC). The two processes are linked and can amplify each other, yet a change in a single marker does not automatically mean an improvement in health.

Results of the latest meta-analysis

In 2026 a pooled analysis of 10 studies involving 532 adults was published. Participants included both healthy people and those with type 2 diabetes, metabolic syndrome, fatty liver disease, after a heart attack or with periodontitis. The studies differed in the dose and form of hesperidin and the duration of use.

After synthesising the results, hesperidin use was associated with lower CRP, hs-CRP and TNF-α values. No clear difference was found in IL-6 across the whole group. Lower IL-6 values were found only in studies involving people with type 2 diabetes or after a heart attack. There were too few data on oxidative stress to draw firm conclusions — only one study assessed MDA and TAC.

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Saffron has been used for thousands of years as a spice and plant material. In 2026 an analysis of 34 studies evaluating its effect on symptoms of depression, anxiety and mood in adults was published.

What saffron is

Saffron is a spice obtained from the cultivated crocus, Crocus sativus L., of the iris family. The plant is small and perennial and grows from an underground corm. It usually flowers in autumn, producing pale-purple or lilac flowers. Inside the flower are three yellow stamens and long, intensely red stigmas.

It is the stigmas — not the whole petals or the stamens — that are hand-picked, dried and sold as true saffron. Crocus sativus does not propagate from seed but by dividing corms. Each plant produces few stigmas, and separating and drying them requires much labour, which contributes to the high price of the spice. Iran remains the most important producer.

Bioactive compounds of saffron

The most characteristic compounds of saffron are the crocins, picrocrocin and safranal. Crocins are water-soluble and are mainly responsible for the intense yellow-orange colour; during digestion they can be converted to crocetin. Picrocrocin is responsible for the bitterish taste, while safranal is a volatile aroma component whose amount increases during drying, among other processes.

The petals have a different chemical profile: they contain flavonoids and anthocyanins, but usually far fewer of the characteristic compounds found in the stigmas. For this reason petal powder, whole stigmas and a standardised extract are not equivalent raw materials.

Saffron and mood regulation

The 2026 review collected results from 34 studies published up to July 2025. The analysis covered 1,769 adults: 895 received saffron and 874 were included in control groups. Follow-up ranged from 4 to 12 weeks, and most studies were carried out in Iran. They included healthy people and patients with, among others, depression, Parkinson's disease, multiple sclerosis, type 2 diabetes or heart disease.

People taking saffron reported milder symptoms of depression and anxiety in self-completed questionnaires than those in placebo groups. On the Beck Depression Inventory the difference averaged 4.39 points, and on the Beck Anxiety Inventory 5.06 points in favour of saffron. However, no clear differences were found in clinician-rated assessments or in overall mood.

There were differences between individual results — in some studies the effect was clear, in others small or absent. Larger changes occurred more often after at least eight weeks. The data did not, however, allow the best dose or type of preparation to be identified.

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