3 Core Supplements for Women in 2025,
expert advice from a Nutritionist
Today we’re covering 3 core supplements for women that can help build a strong base for fab health.
You can think of them as the “nutritional safety net” that supports your wellbeing, even when life gets busy and your diet isn’t perfect. Find out:
- The benefits of a multivitamin and the key nutrients for women after 40.
- What makes omega-3 essential and tips for choosing an effective supplement.
- The value of a magnesium supplement and guidance on how much to take.
Confusion About Women's Supplements After 40
As a Nutritionist, one of the most common questions I hear from women in their 40s is: “What supplements should I actually take?” At this stage of life, subtle changes in energy, sleep, mood and metabolism can make you rethink your nutrition.
To show you what I mean, let’s take Sarah – one of my clients who’s in her mid-40s and facing the same questions you might be asking yourself.
At 44, Sarah felt that she was doing fine — daily walks with her dogs, plenty of fresh air, and a varied vegetarian diet.
She had set a goal to lose a few pounds and had already cut back on snacking. The habit she most wanted to break was mindlessly eating after dinner, even though she wasn’t hungry.
“Now, I’m only eating about 1200-1500 calories, and I’ve stopped snacking on crisps”.
She had a coffee or protein shake for breakfast; a sandwich at lunch – “always with loads of salad”; and a home-made chilli or curry in the evening. As a vegetarian, Sarah ate plenty of veg and legumes or pulses everyday.
Sarah was happy with her healthy eating plan and her daily activity, and then she asked her burning question:
“Nina, can you tell me what supplements I should be taking? I’m so confused that I’ve just stopped taking everything that I have!”
If this sounds familiar, you’re not alone. Many women over 40 are unsure where to start with supplements.
That’s why I created a simple, clear approach: focus on three essentials — a multivitamin, an omega-3 oil and magnesium.
The 3 Core Supplements for Women
Core Supplement #1: The Multivitamin
Do You Really Need A Multivitamin?
Sarah had started taking a multivitamin with thoughts about the peri-menopause in mind. But she was also a bit conflicted. Like many people she wondered whether the old saying was true:
“You don’t need a multivitamin if you’re eating a ‘healthy diet’. Your body will get everything it needs.”
Was Sarah wasting her money and time?
Why It Matters for Women Over 40
I back a ‘food-first’ approach to health, but I believe there are a few reasons why this idea that ‘a healthy diet is enough’ may not serve you well.
- Most adults have a handful of favourite foods that they eat, day after day. Lack of variety may mean you miss out on key nutrients.
- Today foods are grown on nutrient depleted soil, picked before fully ripe, and flown round the world to reach your plate. A recent study highlights how the nutrient content of vegetables and fruit sold in the UK has dropped over the past 80 years, in some instances by as much as 50%.
- Additionally, a healthy diet can come in many forms: you might be intermittent fasting; eating low-GL; eating a high-fat ketogenic diet; or eating a vegetarian diet like Sarah. They all have science-backed health benefits. And they all have potential shortfalls.
Choosing Sarah's Multi...
Sarah was excited to hear about a high-strength one-a-day multivitamin – far more convenient than her current 3-a-day multi.
I wanted good amounts of vitamin B12, iron, zinc and iodine in the formulation. Sometimes, a vegetarian diet is lacking in these.
We also spoke about vitamin D and vitamin K, which work alongside calcium in the diet. Maintaining strong healthy bones would help Sarah stay active in later years.
Quick review: Check your current multi — does it have good amounts of vitamin D3 and vitamin K?
Core Supplement #2: The Omega-3 Oil
Should You Supplement Omega-3?
The family of omega-3 oils have a significant role in your overall health.
They contribute to normal brain function and mood, normal vision, cardiovascular health and joint health, which are all important to maintain as you mature.
These benefits are attributed to the omega-3 fatty acids DHA (docosahexaenoic acid) and EPA (eicosopentaenoic acid) found in fish oil.
However, while brain fog, low mood or aching creaky joints have little appeal, some people shy away from omega oil supplements because of the extra calories involved.
Sarah wanted to lose a few pounds so wasn’t sure if she should include an omega-3 oil.
Why It Matters for Women Over 40
It’s undeniable that omega-3 oils contain calories. But here’s the thing.
Unless you’re on a zero-fat diet (which I would absolutely NEVER recommend), the number of calories in a supplement is pretty small compared to what you get from your food.
For example, if you were eating a Mediterranean Diet – rich in nuts, seeds, oily fish, vegetables, fruit, pulses and lower GL grains – 35% of your daily calorie intake would come from fats and oils. So if you ate 2,000 calories a day, then 700 of your calories could come from dietary fats and oils.
A teaspoon of omega-3 oil contains a mere 45 calories.
There’s evidence that supplementing omega-3 fish oils could help reduce abdominal fat but more studies are needed as overall results on whether taking fish oil helps weight loss are inconclusive.
Choosing An Omega-3 for Sarah
Sarah was enthusiastic about taking an omega-3 oil, particularly as she had been having what she called ‘sticky-brain’ moments. There were times where she was thinking more slowly and as a solicitor, she wanted stay at the top of her game.
We looked at her options, including vegan algae-based omega-3 oils, but Sarah chose a high-quality fish oil with strong levels of EPA and DHA — avoiding cod liver oil, which typically contains much lower amounts.
Quick tip: Omega-3 is only effective if your supplement contains meaningful amounts of EPA and DHA. Don’t just check the total “omega-3” number — look for the breakdown of these two fatty acids.
Core Supplement #3: The Magnesium
Is It Important To Supplement Magnesium?
Sarah had heard that magnesium was good for relaxing muscles.
She had grabbed a magnesium citrate off the shelf but she wasn’t certain if she had the right type or was taking the right amount.
Why It Matters for Women Over 40
Magnesium is quite deservedly known as ‘nature’s valium’. With its role (alongside calcium) in muscle contraction and relaxation, magnesium can have a relaxing, de-stressing and sleep-enhancing effect.
But shopping for magnesium can be overwhelming. How do you know which form to take or the amount that will work for you?.
I recently shared a post on how to choose the best magnesium for sleep.
In “Magnesium, and How to Choose the Best Magnesium for Sleep” you can read more about magnesium’s benefits and find 5 forms rated for sleep.
Fortunately, Sarah was sleeping well.
Choosing A Magnesium For Sarah...
Sarah was thrilled to get the stamp of approval for her chosen magnesium supplement. She was reassured to know she could take it in the evening to help her relax and unwind after a busy day. However, I did encourage Sarah to take 2 capsules instead of 1, to reach the recommended daily dose.
Quick tip: Women aged 40 and over can aim for 265-300 mg of magnesium per day from supplements.
The Takeaway
A few well-chosen supplements could provide a reliable foundation for your health goals. In my practice, the 3 core supplements I recommend most often are:
- A high-strength multivitamin
- An omega-3 oil
- Magnesium
Here’s a quick summary of what to consider when choosing your next supplement.
Choosing your multivitamin…
- Look for good amounts of vitamin D and vitamin K.
- Choose vitamins and minerals in bioavailable forms.
- If multiple daily capsules are a hassle, choose a one-a-day option.
Choosing your omega-3 oil…
- Aim for at least 350 mg EPA and 250 mg DHA per serving. Check the labels, but just so you know, cod liver oil typically has a very low concentration of EPA and DHA per serving (perhaps 40mg of each).
- For vegetarians or vegans, or in cases of allergy, opt for algae-based omega-3
Choosing your magnesium…
- Magnesium glycinate is a popular, well-tolerated and well absorbed choice
- Women over 40 can aim for 265mg per day.
Images by Supliful, Olivia Hutcherson Sarah, Leo Hoho and Mariana Rascal at Unsplash.
I hope this post showed you how to build a core supplement plan. One that’s suitable for women in their 40s and over.
Now I’d like to turn it over to you.
Which of these 3 core supplements will you add to your routine first?
Are you going to take your multi? Maybe you’re planning to add an omega-3 oil or magnesium to your daily stack?
Or you may have a question about something you’ve read.
You can let me know by leaving a comment below right now.