Magnesium is an essential dietary mineral that plays a role in over 300 biochemical reactions in the body. It helps maintain normal nerve and muscle function, supports a healthy immune system, keeps the heart beat steady, and helps bones remain strong. Some good food sources of magnesium include dark leafy greens, beans, fish, nuts, seeds, whole grains, and certain fruits and vegetables like avocados and bananas. But what about blueberries? Are these tiny blue superfoods also rich in magnesium?
The magnesium content of blueberries
Blueberries do contain magnesium, but not in huge amounts compared to some other foods. According to the U.S. Department of Agriculture, one cup of raw blueberries (148 grams) contains 9.0 mg of magnesium. That equates to around 2% of the Daily Value (DV) for magnesium based on a 2000 calorie diet. So while blueberries supply a bit of this mineral, they are not one of the best or most concentrated food sources.
For comparison, here’s how the magnesium content of blueberries stacks up against some other common foods:
| Food | Serving | Magnesium (mg) | DV (%) |
|---|---|---|---|
| Blueberries | 1 cup raw | 9.0 | 2% |
| Spinach | 1 cup cooked | 156 | 39% |
| Almonds | 1 ounce (23 whole nuts) | 80 | 20% |
| Black beans | 1 cup cooked | 120 | 30% |
| Salmon | 3 ounces cooked | 26 | 7% |
| Banana | 1 medium | 32 | 8% |
As you can see, while blueberries do contain magnesium, their levels pale in comparison to leafy greens like spinach, beans, nuts, seeds, whole grains, fish, and certain other fruits and veggies.
Health benefits of magnesium
Since blueberries are not a rich source of magnesium, you may wonder how much they can actually contribute to your daily magnesium intake needs. First, let’s look at why magnesium is so important.
This mineral is involved in numerous vital functions including:
- Protein synthesis
- Regulating blood pressure
- Supporting nerve and muscle function
- Maintaining steady heart rhythm
- Strengthening bones
- Balancing blood sugar
- Sustaining energy levels
- Synthesizing DNA and RNA
Getting sufficient magnesium from your diet helps maintain optimal health and may lower the risk of deficiencies and related issues like muscle cramps, migraines, fatigue, bone loss, and irregular heart rhythms in people prone to them. Magnesium has also been studied for potential roles in reducing anxiety, depression, PMS symptoms, inflammation and aging-related diseases.
Recommended daily intake
How much magnesium should you aim to get each day? Here are the current Daily Values (DVs) for magnesium set by the U.S. Food & Drug Administration:
- Adult men: 400-420 mg/day
- Adult women: 310-320 mg/day
- Pregnant women: 350-400 mg/day
- Teens: 360-410 mg/day
- Children ages 1-13: 80-240 mg/day depending on age
As a general rule, adults should strive for 310-420 mg magnesium per day from food sources like vegetables, legumes, nuts, seeds, and whole grains. People with certain medical conditions or taking medications that interfere with magnesium absorption may need supplementation.
How much magnesium do blueberries provide?
Given that one cup of raw blueberries provides just 9 mg magnesium, a serving would not contribute significantly to meeting daily magnesium needs. You’d have to eat over 30 cups in a day to get the minimum RDA for women!
However, getting small doses of magnesium from multiple sources can help add up over the course of a day. Here’s a look at how much magnesium is provided from one serving of some common high-magnesium foods:
| Food | Serving | Magnesium (mg) |
|---|---|---|
| Spinach | 1 cup cooked | 156 |
| Swiss chard | 1 cup cooked | 150 |
| Pumpkin seeds | 1 ounce | 151 |
| Black beans | 1 cup cooked | 120 |
| Edamame | 1 cup cooked | 99 |
| Quinoa | 1 cup cooked | 118 |
| Almonds | 1 ounce (23 whole nuts) | 80 |
| Cashews | 1 ounce (18 nuts) | 74 |
| Banana | 1 medium | 32 |
| Blueberries | 1 cup | 9 |
While not the most magnesium-dense choice, blueberries can still incrementally add to your daily intake when eaten as part of a balanced diet containing a variety of magnesium-rich foods.
Enhancing magnesium absorption from blueberries
To maximize the magnesium you get from blueberries, there are some preparation tips that can help enhance absorption:
- Eat them raw – Cooking blueberries can degrade some of the magnesium content
- Enjoy with yogurt – The probiotics can aid mineral absorption
- Pair with fat or oil – Fat helps the body utilize magnesium and antioxidants from produce
- Blend into smoothies – Blending breaks down plant cell walls to release nutrients
- Soak before eating – Soaking blueberries overnight helps break down anti-nutrients that can bind minerals
- Reduce phytic acid intake – Phytic acid in grains, nuts, and seeds can inhibit mineral absorption
Practicing these preparation tips when enjoying blueberries can help you get the most magnesium and antioxidant benefits from each serving.
Risks of magnesium deficiency
While a cup of blueberries only provides 2% DV magnesium, consistently falling short on magnesium over time could increase the potential for deficiency. Groups most at risk include:
- Older adults
- People with gastrointestinal disorders
- Those taking medications like diuretics, proton pump inhibitors, and antibiotics
- People with diabetes, endocrine disorders, and alcohol dependence
Signs of magnesium deficiency can include:
- Muscle cramps or twitches
- Fatigue
- Weakness
- Nausea
- Loss of appetite
- Tingling or numbness
- Abnormal heart rhythms
- Low calcium or potassium levels
Chronically low magnesium intake from foods can increase the risks of blood pressure problems, heart disease, osteoporosis, and Type 2 diabetes. That’s why it’s important to get adequate magnesium daily from a varied whole foods diet, including leafy greens, nuts, seeds, beans, fish, avocados, bananas, and yogurt.
Magnesium supplements
If adequate magnesium cannot be obtained through foods or absorption issues exist, magnesium supplements may be warranted. Common forms include magnesium oxide, magnesium citrate, magnesium chloride, magnesium glycinate, and magnesium threonate. Dosages, cost, solubility, and side effects can vary between forms.
Those taking medications should consult their doctor before supplementing to avoid interactions. Possible side effects of too much magnesium include diarrhea, nausea, abdominal cramping, and low blood pressure.
For the majority of healthy people, aiming to meet magnesium needs through food first is ideal rather than relying on supplements alone.
The bottom line
Blueberries contain magnesium, providing 9 mg per one-cup serving. While they don’t belong on the list of the most magnesium-dense foods, they can contribute modestly to daily intake as part of a varied diet.
To help promote your magnesium status, enjoy blueberries with yogurt, add them to smoothies, and soak before eating. Pair them with magnesium-rich foods like leafy greens, beans, nuts, and seeds as well. Obtaining at least 310-400 mg magnesium daily from whole food sources is ideal for health.
While not the richest source, snacking on fresh blueberries is a tasty way to help bump up magnesium levels throughout your day.