The recommended daily intake of vitamin D varies depending on age and health status:

1. Infants (0-12 months): 10 micrograms (400 IU) per day¹.
2. Children (1-13 years): 15 micrograms (600 IU) per day¹.
3. Teens (14-18 years): 15 micrograms (600 IU) per day¹.
4. Adults (19-70 years): 15 micrograms (600 IU) per day¹.
5. Adults (71 years and older): 20 micrograms (800 IU) per day¹.
6. Pregnant and breastfeeding women: 15 micrograms (600 IU) per day¹.

Some health organizations suggest higher daily intakes for certain individuals:

• The Endocrine Society recommends up to 1,500-2,000 IU per day for adults to maintain sufficient vitamin D levels².
• Mayo Clinic suggests that 1,000-2,000 IU per day is generally safe for most adults³.

It's important to discuss with a healthcare provider before starting any supplementation, especially for those with specific health conditions or unique dietary needs³.

Footnotes

1. Office of Dietary Supplements - Vitamin D ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

2. Harvard T.H. Chan School of Public Health - Vitamin D ↩

3. Mayo Clinic Q and A on Vitamin D ↩ ↩²

Melatonin is generally considered safe for short-term use; however, the optimal dosage can vary by individual. Typical dosages range between 0.5 mg to 5 mg taken about 30 minutes to an hour before bedtime¹.

1. Short-Term Insomnia in Adults: The usual dose is 2 mg of slow-release melatonin taken 1 to 2 hours before bedtime².
2. Jet Lag: Typically, 3 mg of melatonin is recommended, but doses can go up to 6 mg if needed².
3. Children: Lower doses are recommended for children, often starting from 0.5 mg to 1 mg, and can go up to 3 mg³. Always consult a healthcare provider before giving melatonin to children.

What is considered too much?

Taking higher doses than recommended can be counterproductive and may lead to side effects such as daytime drowsiness, dizziness, headaches, and mood changes⁴. Higher doses (above 5 mg) do not necessarily improve sleep and could lead to an increased risk of adverse effects⁴:

• For Adults: It is generally advised to keep the dosage below 10 mg per day. Doses above 10 mg may increase the risk of harmful effects without additional benefits in sleep improvement⁴.
• For Children: Consult with a healthcare provider for appropriate dosing.

Serious side effects may include:

• Worsening of seizures,
• Changes in heart rate and blood pressure,
• Decrease in glucose tolerance,
• Possible drug interactions for people taking medications for seizure disorders, antidepressants, or blood thinners⁵.

Always discuss with a healthcare provider before starting melatonin supplements, especially for long-term use or if you have underlying health conditions⁵.

Footnotes

1. MedlinePlus - Melatonin ↩

2. NHS - How and when to take melatonin ↩ ↩²

3. Mayo Clinic Minute: What to consider before using melatonin supplements for sleep ↩

4. NCBI - Melatonin StatPearls ↩ ↩² ↩³

5. Mayo Clinic Minute: What to consider before using melatonin supplements for sleep ↩ ↩²