什麼是血清素?

Overview

What is serotonin?

Serotonin, also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter. It also acts as a hormone.

As a neurotransmitter, serotonin carries messages between nerve cells in the brain (central nervous system) and throughout the body (peripheral nervous system). These chemical messages tell your body how to function.

Serotonin plays a variety of roles in your body, including affecting learning, memory, well-being, and regulating body temperature, sleep, sexual behavior, and hunger. A lack of adequate serotonin is thought to lead to depression, anxiety, mania, and other health conditions.

Most of the serotonin found in your body is found in your gut. About 90% of serotonin is found in the cells lining the gastrointestinal tract. It is released into your blood circulation and absorbed by platelets. Only about 10% is produced in your brain.

Serotonin is made from the essential amino acid tryptophan. An essential amino acid means your body cannot make it. It has to be obtained from the food you eat.

What does serotonin do in my body?

Serotonin plays an important role in many functions of your body:

  • Mood: Serotonin in the brain regulates your mood. It is often referred to as the body's natural "feel good" chemical. When serotonin is at normal levels, you feel more focused, emotionally stable, happier, and calmer. Low serotonin levels are associated with depression. Many medications used to treat anxiety, depression, and other mood disorders are often designed to increase serotonin levels in the brain.
  • Digestion: Most of the body’s serotonin is found in the gastrointestinal tract, where it helps control bowel function and plays a protective role. Your gut can increase the release of serotonin, which speeds up digestion and clears your body of irritating foods or toxic products. Serotonin can also reduce appetite when eating.
  • Nausea: When serotonin is released into the intestines faster than digestion can cause a feeling of nausea. The chemical message is received by your brain and you interpret it as nausea. Many medications used to reduce feelings of nausea and vomiting target specific serotonin receptors in the brain.
  • Sleep: Serotonin, along with another neurotransmitter, dopamine, affects the quality of your sleep. Your brain also needs serotonin to produce melatonin, a hormone that regulates the sleep-wake cycle.
  • Wound healing: Platelets in the blood release serotonin, which helps wounds heal. It also causes the tiniest blood vessels to narrow, which slows blood flow and contributes to the formation of blood clots. This is an important process in wound healing.
  • Bone health: Serotonin levels may affect bone density. High levels of serotonin in the gut may cause bones to weaken, leading to fractures and osteoporosis.
  • Sexual health: Serotonin, along with the neurotransmitter dopamine, also has an impact on sexual desire.

What problems are associated with low serotonin levels?

Low serotonin levels may be linked to many health conditions, including:

  • Depression and other emotional problems.
  • anxiety.
  • Sleep problems.
  • Digestive problems.
  • Suicidal behavior.
  • Obsessive-compulsive disorder.
  • Post-traumatic stress disorder.
  • Panic Disorder.
  • Schizophrenia.
  • phobia.

Scientists still have a lot to learn about serotonin's role in the body and disease.

What causes low serotonin levels?

Low serotonin levels often have more than one cause. Technically, serotonin levels are low because:

  • Your body cannot produce enough serotonin.
  • Your body cannot use serotonin efficiently. This happens if you don't have enough serotonin receptors or the receptors aren't functioning properly.

What can I do to increase serotonin levels?

Ways to increase serotonin levels include:

  • Eat more tryptophan-containing foods.
  • Get more sunlight.
  • Take certain supplements.
  • Get more exercise and lower your stress levels.

Foods that increase serotonin levels

Many foods naturally contain tryptophan, the amino acid that produces serotonin. You can try to increase serotonin levels by eating foods containing tryptophan, such as:

  • salmon.
  • Egg
  • cheese.
  • turkey
  • Tofu
  • pineapple.
  • Nuts, oats and seeds

Eating tryptophan-rich foods by itself does not necessarily increase serotonin levels. This is a complex process. Your body needs carbohydrates to release insulin, which is needed to absorb amino acids. Even if tryptophan does enter your bloodstream, it must compete with other amino acids to be absorbed by your brain. Scientists are still studying how consuming tryptophan-containing foods might increase serotonin levels.

Sunlight

Not getting enough sun exposure may cause the mood disorder Seasonal Affective Disorder in some people. Try getting 10 to 15 minutes of sunlight each day to not only boost your serotonin levels, but also your vitamin D levels. If you live in an area without access to natural sunlight, consider using light therapy to get your daily dose of sunlight.

supplements

Some dietary and herbal supplements also increase serotonin levels. These include:

  • Dietary supplements: tryptophan, probiotics.
  • Herbal supplements: include ginseng, St. John's wort, Syrian rue and nutmeg.

exercise

Regular exercise is known to increase serotonin levels. Thirty minutes of aerobic exercise five times a week plus strength training twice a week can improve mood disorders and heart health.

What drugs increase serotonin levels?

Serotonin receptors are a common target for the pharmaceutical industry because many health conditions are affected by serotonin. Some common medications that increase serotonin levels include:

Several different classes of antidepressant drugs block the reabsorption and recycling of serotonin, allowing more serotonin to remain in the brain. Drugs that work in this way include selective serotonin reuptake inhibitors (such as paroxetine [Paxil®]), serotonin-norepinephrine reuptake inhibitors (such as venlafaxine [Effexor®]), and Tricyclic antidepressants (such as amitriptyline [Elavil®]). Another type of antidepressant medication is a monoamine oxidase inhibitor (such as phenelzine [Nardil®]), which blocks the enzyme that breaks down serotonin.

Many other drugs used to treat a variety of conditions also increase serotonin. Some of these medications include triptan headache medications, opioid pain relievers, cough suppressants containing dextromethorphan, and anti-nausea medications.

What problems can high serotonin levels cause?

Serotonin syndrome is a condition that occurs when serotonin levels rise too much. This usually occurs if you increase your dose of a drug known to increase serotonin levels or take another drug known to increase serotonin levels.

Mild symptoms include tremors, profuse sweating, confusion, restlessness, high blood pressure, muscle twitching and diarrhea. Severe symptoms include high fever, seizures, fainting and abnormal heartbeats.

If serotonin syndrome is severe and not detected early and treated quickly, it can be fatal.

Other FAQs

What is the difference between dopamine and serotonin?

Dopamine and serotonin are both neurotransmitters. This means that they are carriers of chemical messages between nerve cells in the brain and between other areas of the body. Both are also considered "happy hormones" as they both play a role in positive moods and moods. Serotonin is associated with happiness, focus, and calmness. Dopamine is associated with reward and motivation. Dopamine and serotonin have also been linked to some mental health conditions, including depression and mood disorders.

Dopamine and serotonin also have some different functions. Dopamine controls body movement and coordination. Serotonin helps regulate digestive functions, including bowel function and appetite. Dopamine causes hunger, while serotonin suppresses this feeling. Dopamine is primarily stored in your brain, while serotonin is primarily stored in your gut.

Sometimes these neurotransmitters work together to maintain chemical balance in the body. Sometimes, an imbalance can lead to overproduction of another neurotransmitter. Too much or too little of any of these can lead to physical and psychological symptoms.

Comment

Serotonin plays a key role in body functions such as mood, sleep, appetite, anxiety, digestion, blood clotting, and libido. If you have a medical condition that affects or is affected by serotonin, ask your healthcare provider what you need to know about serotonin. To prevent fluctuations in serotonin levels in your body and reduce the possibility of drug interactions, do not stop taking your medications, change your dosage, or take dietary or herbal supplements without first talking with your healthcare provider.

Review

All comments are moderated before being published

HealthyPIG Magazine

View all
小朋友叫唔應?可能唔係無禮貌,而係科學:專注時真係聽唔到你

小朋友叫唔應?可能唔係無禮貌,而係科學:專注時真係聽唔到你

小朋友一睇YouTube、打機、畫畫,突然叫佢,佢完全聽唔到。係咪扮聾?係咪發展遲緩?抑或專注力問題? 研究顯示,大部分情況完全正常,與腦部的「選擇性注意力(Selective Attention)」同「過度專注(Hyperfocus)」有關,不代表有疾病。 什麼是「選擇性注意力」?(Sele...
高血壓|隱形殺手的成因、統計數據與科學研究

高血壓|隱形殺手的成因、統計數據與科學研究

  高血壓|隱形殺手的成因、統計數據與科學研究 快速導讀 高血壓係全球最普遍、但最容易被忽視嘅慢性病之一。 超過一半患者完全無症狀,但長期會破壞血管、增加中風同心臟病風險。 主要成因包括:高鹽、肥胖、缺乏運動、低鉀、飲酒、睡眠窒息症、壓力、吸煙、腎病等。 全球研究顯示:高鹽攝取加上肥胖...
為何肺癌早期大多沒有症狀?科學原理、風險因素與早期發現方法全解析

為何肺癌早期大多沒有症狀?科學原理、風險因素與早期發現方法全解析

肺癌一直是全球最常見、死亡率最高的癌症之一。令人憂心的是,大部分肺癌患者在早期(第一、二期)都沒有明顯症狀,往往直到腫瘤擴散、壓迫周邊結構或影響呼吸功能後才被發現。本文以科學角度深入講解:為何肺癌早期「靜悄悄」、身體不察覺?身體內部究竟發生了甚麼? 亦會加入實際的自我檢查策略與醫學建議。 一...
黑眼圈成因全解析:從生理、生活習慣到醫學對策

黑眼圈成因全解析:從生理、生活習慣到醫學對策

前言:為何黑眼圈總是揮之不去? 「黑眼圈」係現代人嘅常見問題之一。無論係通宵工作、壓力過大、過敏,甚至遺傳因素,都可能令眼底皮膚變黑或出現陰影。雖然多數情況屬於美容問題,但有時亦可能反映身體狀況,例如貧血、睡眠質素差、血液循環不良等 [1]。  一、黑眼圈的主要類型與成因 色素型黑眼圈(Pi...
智慧手錶 vs 專用 O₂Ring 血氧儀:血氧監測能力的科學比較

智慧手錶 vs 專用 O₂Ring 血氧儀:血氧監測能力的科學比較

1. 前言 血氧飽和度(SpO₂)是評估呼吸、循環系統狀態的重要指標。近年來,市面上兩大類可穿戴設備用於血氧監測: 智慧手錶(如 Samsung Watch、Apple Watch) 專用血氧監測設備(如 O₂Ring、指夾式脈搏血氧儀) 兩種設備的設計目的、測量方式、準確性、監測...
血氧飽和度、氧氣下降與「警戒線」的科學探討

血氧飽和度、氧氣下降與「警戒線」的科學探討

1. 前言 血氧飽和度(SpO₂)即血液中氧合血紅蛋白佔總血紅蛋白的百分比,是臨床及居家監測呼吸、循環功能的重要指標。當血氧飽和度下降,可能反映體內氧的供應或運送出現問題(低氧血症、hypoxemia)或更廣泛的組織缺氧(hypoxia)[1][2]。本文旨在探討: 血氧飽和度正常範圍與變...
冰敷(Cold Therapy)真正作用全面解析:止痛、減腫,還是幫助修復?|科學視角 + 實證文獻

冰敷(Cold Therapy)真正作用全面解析:止痛、減腫,還是幫助修復?|科學視角 + 實證文獻

冰敷(Ice Pack / Cold Therapy / Cryotherapy)係好多運動、急性受傷(如扭傷、撞擊、肌肉拉傷)時的第一時間處理方法。但不少人會疑惑: 「冰敷純粹止痛,定係真係會幫助組織修復?」「冰敷幾耐?冰敷幾多日?會唔會影響身體自然修復?」 本文從科學、醫學、運動治療角度,...
長時間保持同一姿勢後關節痛、僵硬、郁唔到:成因、科學解釋與改善方法

長時間保持同一姿勢後關節痛、僵硬、郁唔到:成因、科學解釋與改善方法

前言:為何「坐耐、蹲耐、跪耐」之後會痛? 無論係坐喺電腦前、跪低執嘢、長時間翹腳、側睡又唔郁——好多人體驗過一樣情況: 「一動就痛、一企起身腳軟、膝蓋直唔到、關節卡卡聲,又或者要行幾步先鬆返。」 其實呢種情況係非常普遍,而且通常並非關節已經壞死,而係 和關節生理、滑液循環、血液供應、肌肉張力 ...
魚醒味的科學:成因、風險與處理方法全面解析

魚醒味的科學:成因、風險與處理方法全面解析

「魚醒味」是華人烹飪文化中常見的說法,用以描述魚類在 解凍、切片或加熱後所突然出現的腥味、血水味或脂肪味。此現象並不代表食材變壞,但背後牽涉到蛋白質變化、脂肪氧化與揮發性化合物釋放等多種科學機制。本文將以科學角度剖析魚醒味的成因,並提供實證方法降低這種味道,同時探討其安全性。 🧪 什麼是「魚...