Most of us know we are supposed to get our vitamins. Rather fewer of us could name what any particular one actually does, or how much of it we are meant to be getting. And if you have ever picked up a supplement bottle and tried to work out whether 1000 mg of something is sensible or silly, you will know the labels are not much help.
Here is a plain-English guide to the thirteen essential vitamins — what each one does, how much New Zealand actually recommends, and where to find it in food you can buy at any supermarket.
Key takeaways
- There are 13 essential vitamins. Your body cannot make enough of them on its own, so they have to come from food.
- They split into two groups: water-soluble (C and the B vitamins), which are not stored and need topping up regularly, and fat-soluble (A, D, E, K), which are stored in your liver and fatty tissue.
- New Zealand uses the Australia & New Zealand Nutrient Reference Values, which differ from the American figures you will see on a lot of international websites. NZ recommendations are lower for several nutrients.
- Most people meet their needs through a varied diet. Supplements fill gaps — they do not replace food.
What are vitamins?
Vitamins are organic compounds your body needs in small amounts to function — for growth, repair, energy release, immune function and a long list of other jobs. The defining feature is that your body either cannot make them at all, or cannot make enough, so they have to come in from outside.
"Small amounts" is doing real work in that sentence. Most vitamins are measured in milligrams or micrograms. A microgram is a millionth of a gram. You need a genuinely tiny quantity of vitamin B12 each day, but you do need it every day.
Water-soluble vs fat-soluble: the one distinction worth remembering
If you take nothing else away, take this.
Water-soluble vitamins — vitamin C and all eight B vitamins — dissolve in water. Your body does not store them in any meaningful way. Whatever you do not use gets passed out in your urine, usually within hours. That means intake matters day to day, and it also means it is quite hard to overdo them from food alone.
Fat-soluble vitamins — A, D, E and K — dissolve in fat and are stored in your liver and fatty tissue. Because they accumulate, you have a buffer: you do not need a perfect intake every single day. The flip side is that it is possible to take too much over time, particularly from high-dose supplements, so these are the ones to be careful with.
This distinction explains a lot of otherwise confusing advice. It is why a very high vitamin C supplement mostly ends up down the toilet, and why "more is better" is genuinely bad advice for vitamin A.
The 13 essential vitamins and how much New Zealand recommends
The amounts below are the Australia & New Zealand Nutrient Reference Values for adults aged 19–50. Where men and women differ, both are shown. RDI means Recommended Dietary Intake; AI means Adequate Intake, used where there was not enough evidence to set an RDI.
Water-soluble — top up daily
Vitamin C ascorbic acid
RDI 45 mg
Collagen formation, immune function, and helping you absorb iron from plant foods.
Find it in: Kiwifruit, capsicum, broccoli, blackcurrants, feijoas, citrus
Vitamin B1 thiamin
RDI 1.2 mg men · 1.1 mg women
Releasing energy from the food you eat, and nerve function.
Find it in: Wholegrain bread, pork, legumes
Vitamin B2 riboflavin
RDI 1.3 mg men · 1.1 mg women
Energy metabolism, plus skin and eye health.
Find it in: Milk, cheese, eggs, green vegetables
Vitamin B3 niacin
RDI 16 mg men · 14 mg women
Energy metabolism, skin, and the nervous system.
Find it in: Chicken, beef, fish, peanuts
Vitamin B5 pantothenic acid
AI 4 mg
Making and breaking down fats.
Find it in: Meat, eggs, avocado, wholegrains — it is widely available
Vitamin B6 pyridoxine
RDI 1.3 mg
Protein metabolism, red blood cells, and brain function.
Find it in: Fish, chicken, bananas, potatoes
Vitamin B7 biotin
AI 30 µg
Fat and carbohydrate metabolism.
Find it in: Eggs, nuts, seeds, salmon
Vitamin B9 folate
RDI 400 µg DFE
Cell division and red blood cells. Critical before and during early pregnancy.
Find it in: Leafy greens, legumes, fortified bread
Vitamin B12 cobalamin
RDI 2.4 µg
Red blood cells and nerve function.
Find it in: Meat, fish, dairy, eggs — worth watching on a vegan diet
Fat-soluble — stored by your body
Vitamin A retinol
RDI 900 µg men · 700 µg women
Vision, immune function, and skin.
Find it in: Kūmara, carrots, liver, eggs, dairy
Vitamin D
AI 5 µg
Calcium absorption, and bone and muscle health.
Find it in: Sunlight on skin; oily fish, eggs, fortified spreads
Vitamin E
AI 10 mg men · 7 mg women
Protecting your cells from oxidative damage.
Find it in: Nuts, seeds, vegetable oils, avocado
Vitamin K
AI 70 µg men · 60 µg women
Blood clotting and bone health.
Find it in: Broccoli, spinach, silverbeet, cabbage
Source: Nutrient Reference Values for Australia and New Zealand, National Health and Medical Research Council and the New Zealand Ministry of Health. Values shown are for adults 19–50; requirements differ for children, older adults, and during pregnancy and breastfeeding.
Why New Zealand's numbers differ from what you read online
If you compare the amounts above against an American health site, several figures will look low. That is not an error. Australia and New Zealand set their own Nutrient Reference Values, and the committees that set them weighed the evidence differently from their United States counterparts. Vitamin C is the clearest example: the NZ recommendation for adults is well below the American one.
It is worth knowing this, because a lot of supplement marketing quotes percentages of the US figure. A product claiming to deliver "over 1000% of your daily vitamin C" is telling you something about the size of the dose, not about whether you need it.
What vitamin deficiency actually looks like
True clinical deficiency is uncommon in New Zealand, but low intake is not, particularly through winter and among people on restricted or low-variety diets.
The everyday signs tend to be vague rather than dramatic — persistent tiredness, dull skin, hair that breaks easily, bruising more readily than usual, wounds healing slowly, mouth ulcers, or feeling run-down more often than seems normal.
The honest caveat: every one of those has dozens of possible explanations, most of which are not about vitamins at all. Symptoms are a prompt to look more closely, not a diagnosis. If something has been going on for a while, see your GP.
How would you know where you stand?
The most useful place to start is the least technical: look at what you actually eat across a normal week. If fresh fruit and vegetables are thin on the ground, that is more informative than any test.
Beyond that, your GP can arrange laboratory testing where it is clinically warranted. At-home wellness tests sit in a different category — they are not diagnostic, but they can give you a regular, low-effort read on a handful of markers so you can see whether things are trending in the right direction.
Curious where you sit? The Vivoo Wellness Test reads several wellness parameters from a single strip — including vitamin C, hydration, pH, calcium, magnesium, ketones, oxidative stress and sodium — and the app tracks each result over time.
Frequently asked questions
How many essential vitamins are there?
Thirteen: vitamin A, the eight B vitamins (B1 thiamin, B2 riboflavin, B3 niacin, B5 pantothenic acid, B6, B7 biotin, B9 folate and B12), vitamin C, vitamin D, vitamin E and vitamin K.
What is the difference between water-soluble and fat-soluble vitamins?
Water-soluble vitamins (C and the B group) dissolve in water, are not stored by the body, and any excess is passed out in urine — so they need topping up regularly. Fat-soluble vitamins (A, D, E and K) are stored in the liver and fatty tissue, which gives you a buffer but also means they can build up to excessive levels from high-dose supplements.
Why are New Zealand's recommended vitamin amounts different from American ones?
New Zealand and Australia use their own Nutrient Reference Values, set by the National Health and Medical Research Council with the NZ Ministry of Health. The expert committees interpreted the evidence differently from their United States counterparts, so several figures are lower. Vitamin C is the most noticeable example.
Do I need a multivitamin?
Most people eating a varied diet meet their needs from food. Supplements are useful for filling identified gaps — for example vitamin B12 on a vegan diet, or folate before and during early pregnancy — rather than as general insurance. If you are unsure, talk to your GP or a registered dietitian.
Can you take too many vitamins?
Yes, particularly the fat-soluble ones (A, D, E and K), because your body stores them. Excess water-soluble vitamins are largely excreted, so they are harder to overdo from food, though very high supplement doses can still cause problems. The Nutrient Reference Values include Upper Levels of Intake for this reason.
Disclaimer: This article is general information and is not medical or dietary advice. Nutrient Reference Values shown are for adults aged 19–50 and differ for other groups, including children, older adults and during pregnancy and breastfeeding. Vivoo measurements are not intended for medical use and are designed for general fitness and wellness purposes only. They are not intended to diagnose, treat, cure or prevent any disease. If you have concerns about your health or ongoing symptoms, please speak with your doctor or a registered healthcare professional.