For most people, a varied and well-balanced diet can provide most of what the body needs.

Regular protein foods. Fruit and vegetables. Potatoes and whole grains. Dairy or fortified alternatives. Nuts and seeds. Legumes. Eggs. Seafood if you eat it.

Nothing particularly exciting — but it works.

Where things can become more complicated is when your needs or circumstances change.

Hard training can increase energy demands and losses through sweat. Dieting for long periods can reduce the amount of micronutrients coming in simply because you're eating less food. Gastrointestinal conditions can affect absorption. Certain medications can influence nutrient status. Pregnancy changes requirements dramatically. Vegan or very restrictive diets require more planning. Illness, recovery, heavy sweating and prolonged periods of poor appetite can also make certain gaps more likely.

And high-stress periods can make things harder indirectly too — sleep gets worse, appetite changes, meals become less consistent and food quality often drops.

That doesn't automatically mean you need supplements.

It means it's worth looking at the whole picture.

DON'T GUESS A DEFICIENCY

This is probably the most important point in this blog post.

Don't start taking high doses of vitamins or minerals simply because you've read that they're "good for you."

Essential doesn't mean harmless in unlimited amounts.

Your body needs zinc. Too much zinc can interfere with copper absorption.

Your body needs iodine. Too much iodine can disrupt thyroid function in susceptible people.

Your body needs vitamin D. Excessive supplementation over time can cause dangerously high calcium levels.

Iron is essential for carrying oxygen — but taking iron when you don't need it isn't something we'd recommend either.

More is not automatically better.

When there is a genuine reason to suspect a deficiency, use appropriate testing and professional guidance where it makes sense instead of guessing.

And there's an important detail here: not every nutrient is perfectly assessed with a simple blood test. Magnesium is a good example — serum magnesium doesn't always reflect total body stores particularly well.

So the approach should be:

diet first → look at symptoms and risk factors → test appropriately when indicated → supplement for a reason.

Not:

see Instagram post → order six supplements.

Now let's look at some of the nutrients worth having on your radar.

1. OMEGA-3

When we talk about omega-3 here, we're mainly talking about EPA and DHA — the forms found predominantly in seafood.

They play important roles in cardiovascular health, brain function and eye health.

Plant foods such as chia, flax and walnuts contain ALA, which is also an omega-3, but our bodies only convert a relatively small proportion into EPA and DHA.

Make it practical

You don't need salmon every night.

A very realistic target is around two servings of oily fish per week.

Think:

• Salmon

• Mackerel

• Sardines

• Herring

• Trout

Easy win: salmon for dinner one night and sardines, trout or mackerel another day.

If you don't eat fish at all, that's where an EPA/DHA supplement — including algae-based options — may be worth discussing.

2. MAGNESIUM

Magnesium is involved in hundreds of reactions throughout the body, including energy production, muscle function and normal nerve signalling.

This is also one of those nutrients that gets marketed very aggressively.

Yes, magnesium matters.

No, that doesn't mean everybody automatically needs a large magnesium supplement.

Start with your food

Great sources include:

• Pumpkin seeds

• Chia seeds

• Almonds

• Cashews

• Beans

• Lentils

• Whole grains

• Leafy greens

• Dark chocolate

Make it practical: Add one proper serving of nuts or seeds most days.

For example:

Greek yogurt + chia + berries.

Oats + pumpkin seeds.

A handful of almonds with fruit.

Throw lentils or beans into lunch.

Small habits add up much faster than people think.

3. POTASSIUM

Potassium is hugely important for muscle contraction, nerve function, fluid balance and blood-pressure regulation.

And despite what fitness culture sometimes makes it sound like, potassium isn't just bananas.

Potatoes are excellent.

So are:

• Beans

• Lentils

• Spinach

• Avocado

• Yogurt

• Fruit

• Dried fruit

Make it practical

Instead of thinking:

"What is the highest-potassium food?"

Think:

"How many potassium-rich foods appear across my day?"

A potato with lunch, fruit with breakfast, and beans or vegetables at dinner already puts you in a much better position.

Potassium is also a good example of why we prefer food first rather than casually supplementing large amounts.

4. CALCIUM

Most people associate calcium with bones, but your muscles also require calcium every time they contract.

It also plays a role in normal nerve signalling.

Useful sources include:

• Milk

• Greek yogurt

• Cheese

• Calcium-set tofu

• Sardines with bones

• Fortified plant milks

Make it practical

Instead of trying to get a day's worth at once, spread calcium-containing foods across the day.

For example:

Breakfast: Greek yogurt

Lunch: some cheese or fortified alternative

Dinner: tofu, dairy or another calcium-rich food

Simple.

5. VITAMIN D

Vitamin D supports bone health, immune function and muscle function.

But vitamin D is slightly different from most of the nutrients in this article because food isn't always enough to reliably maintain optimal status.

Your vitamin D level can be influenced by:

• Sun exposure

• Season

• Latitude

• Skin pigmentation

• Age

• Lifestyle

• How much time you spend indoors

Oily fish and fortified foods can help, but this is one nutrient where testing can be particularly useful when deficiency is suspected or you're considering significant supplementation.

Don't assume you need a huge dose because it's winter.

Find out whether there's actually a problem.

6. VITAMIN B12

Vitamin B12 is required for red blood cell formation, normal nervous-system function and DNA production.

It is naturally concentrated mainly in animal foods:

• Shellfish

• Fish

• Meat

• Eggs

• Dairy

If you're eating a varied omnivorous diet, B12 is often fairly straightforward to cover.

If you eat little or no animal food, it becomes much more important to think about fortified foods or supplementation.

This is a good example of nutrition needing to match the person, rather than everyone following the same plan.

7. FOLATE

Folate is important for DNA synthesis and the creation of new cells.

You'll find plenty of it in foods that are already worth eating for dozens of other reasons:

• Lentils

• Beans

• Edamame

• Spinach

• Asparagus

• Leafy greens

• Avocado

Make it practical

Have legumes several times per week.

One meal with lentils, spinach and potatoes isn't just giving you folate.

You're getting potassium, magnesium, fibre, iron, carbohydrates and plenty of other useful nutrients at the same time.

That's exactly why we prefer thinking in terms of foods and meals rather than isolated nutrients.

8. ZINC

Zinc supports immune function, wound healing and protein synthesis.

Good sources include:

• Oysters

• Beef

• Meat

• Seafood

• Dairy

• Pumpkin seeds

• Chickpeas

• Beans

Zinc from animal foods tends to be more readily absorbed than zinc from plant foods because compounds such as phytates can reduce absorption.

That doesn't make plant sources "bad."

It just means someone eating entirely plant-based may need to pay a little more attention to intake.

And again: don't start high-dose zinc just because you train hard.

Long-term excessive zinc can create other nutrient problems, particularly by interfering with copper.

9. VITAMIN C

Vitamin C supports collagen production, antioxidant defence and iron absorption.

And fortunately, it's really not difficult to find.

Some great sources:

• Red bell peppers

• Kiwi

• Strawberries

• Citrus

• Broccoli

• Guava

One useful trick

If you're eating a plant-based source of iron, pair it with something rich in vitamin C.

For example:

Lentils + peppers

Beans + tomatoes

Oats + berries

Vitamin C can improve the absorption of non-heme iron from plant foods.

That's a practical nutrition strategy we actually care about.

10. IODINE

Iodine is required to produce thyroid hormones, which influence metabolism and many processes throughout the body.

Sources include:

• Seafood

• Dairy

• Eggs

• Iodized salt

And here's a small detail many people don't realise:

Sea salt, Himalayan salt and fancy specialty salts are not automatically good sources of iodine.

If you're already salting your food, using iodized salt can be one extremely simple way of helping cover your iodine intake.

That does not mean adding more salt to your diet.

It means making the salt you're already using work a little harder.

And please don't start taking huge kelp or iodine supplements because you've heard they're "good for the thyroid."

Too little iodine can cause problems.

Too much can as well.

WHAT THIS LOOKS LIKE IN REAL LIFE:

This doesn't require a perfect diet.

A normal day could be:

Breakfast

Greek yogurt + berries + kiwi + chia seeds

Lunch

Potatoes + spinach + chicken, beef, tofu or beans

Snack

Fruit + almonds or pumpkin seeds

Dinner

Salmon + rice + vegetables

Cooking:

A sensible amount of iodized salt

Now look at what you've covered without trying very hard:

Omega-3.

Magnesium.

Potassium.

Calcium.

Vitamin D.

B12.

Folate.

Zinc.

Vitamin C.

Iodine.

And you're getting protein, carbohydrates, fibre and healthy fats at the same time.

That's what a good diet is supposed to do.

BUT YOUR NEEDS CAN CHANGE!

This is another thing we think gets missed.

What works when you're eating at maintenance, sleeping eight hours and training three days per week may not feel exactly the same during a hard training block, a long calorie deficit or a stressful period of life.

Your nutrition doesn't exist in a vacuum.

Things like:

training volume, energy intake, heavy sweating, illness, pregnancy, gastrointestinal conditions, medications, dietary restrictions, poor appetite and recovery demands can all change the nutritional picture.

Sometimes the answer is a supplement.

But quite often the first answer is much less exciting:

eat enough food.

Get enough protein.

Eat carbohydrates to support your training.

Eat fruit and vegetables.

Get some healthy fats.

Include several different protein sources.

Eat nuts, seeds and legumes.

Include dairy or fortified alternatives.

Eat seafood if that's part of your diet.

And don't eat the exact same five foods every single day.

FOOD FIRST DOESN'T MEAN SUPPLEMENTS ARE BAD

We use supplements too.

There are absolutely situations where supplementation makes sense.

But we want there to be a reason behind it.

Maybe your diet genuinely can't provide enough.

Maybe you're vegan.

Maybe bloodwork shows a deficiency.

Maybe absorption is impaired.

Maybe a doctor or dietitian has identified a higher requirement.

Maybe you're in a situation where food alone simply isn't practical.

That's different from assuming that if 100% of the recommended amount is good, 500% must be five times better.

Your body doesn't work like that.

Vitamins and minerals are incredibly important because they have biological effects.

And that's exactly why taking too much of certain ones can also have biological effects you didn't want.

THE BIG PICTURE

Don't look at these graphics and think you now need to eat liver, oysters, sardines, pumpkin seeds, and guava every day. 😂

They're there to show you where these nutrients come from.

Your job isn't to build the mathematically perfect plate.

It's to build a diet with enough variety that you don't have to micromanage every vitamin and mineral in the first place.

For most healthy people, eating enough food and regularly including protein foods, fruits, vegetables, legumes, nuts and seeds, dairy or fortified alternatives, whole-food carbohydrates and seafood where appropriate will get you a very long way.

Then if something feels off, your circumstances change, or you have a genuine reason to suspect a deficiency:

investigate it. Don't guess.

Test where appropriate, look at the whole picture and supplement with a purpose.

That's nutrition we can actually use.