Selenium is an essential trace mineral that is only needed in minute amounts. However, this trace element is small but mighty.
What is Selenium Good For in the Body?
- We need selenium to convert T4 thyroid hormone into its active form known as T3. Lower selenium levels have been associated with autoimmune thyroid disorders like Hashimoto’s thyroiditis.
- Selenium is thought to be protective against cancers. Studies have shown an inverse relationship between selenium levels and someone’s risk for colon, prostate, lung, bladder, gastric, skin, and esophageal cancers.
Because of its role as an antioxidant, selenium has been shown to prevent heart disease and cognitive decline, minimise asthma symptoms, and support the immune system.
- Selenium helps orchestrate apoptosis or the regulated cell death of old and defective cells.
- We also need selenium to produce the body’s master antioxidant, glutathione.
- Men need ample amounts of selenium to support the healthy motility and development of sperm.
- The body needs selenium to make tiny proteins that protect against cell damage and infection and help to make DNA.
- Selenium is often plentiful in seafood and is known to help you detoxify the mercury found in some fish.
- What is Selenium Good For in the Body?
- Selenium Rich Foods
- Selenium-Rich Recipes
- What Are The Symptoms of Selenium Deficiency?
- Factors That Increase Demand For Selenium
- Satiety Response to High Selenium Foods
- Selenium Toxicity
- Selenium Stretch Target
- Availability of Selenium in the Food System
- Synergistic Nutrients
- The Nutrient Profile of High Selenium Foods
- How Can I Calculate my Selenium Intake?
Selenium Rich Foods
Fortunately, selenium is usually found readily within the soils, so plants and animals can get enough to selenium-rich foods for human consumption. As a result, selenium foods are scattered throughout the plant and animal kingdoms, although they’re most abundant in foods from the sea. Here, it is usually found alongside its synergist, iodine.
Although selenium is found consistently in seafood, it is found in its highest concentration in Brazil nuts. This makes it easy to get selenium if you’re following a vegan or vegetarian diet.
Other popular selenium-rich foods are listed below.
Animal
- pork
- beef liver
- chicken (light meat)
- egg
- cheese
- milk
- ground beef
- turkey
- cottage cheese
Seafood
- shrimp
- salmon
- tuna (yellowfin)
- halibut
- sardines
- crab
- oysters
- clams
Fats
- Brazil nuts
- bacon
- cashews
- sunflower seeds
Vegetables
- spinach
- asparagus
- mushrooms
- broccoli
- garlic
- flax seeds
- kale
- sauerkraut
- cabbage
- cauliflower
- lettuce
- cucumber
- onion
- zucchini
Other Plant Foods
- baked beans
- oats
- brown rice
Check out the top foods high in selenium at Nutrient Optimiser for more detail.
Selenium-Rich Recipes
Some examples of selenium-rich NutriBooster recipes include:
- oysters mignonette
- blackberry & avocado salad
- quick fish salad with tuna
- salade Nicoise (pictured below)
- quick fish salad with mussels
What Are The Symptoms of Selenium Deficiency?
A lack of selenium is associated with:
- hypertension,
- atherosclerosis,
- hypothyroid,
- lowered immunity,
- impaired immune responses,
- muscle weakness,
- muscle pain,
- symptoms of asthma,
- poor cognition,
- Autoimmune (Hashimoto’s) thyroiditis,
- heart failure, and
- coronary heart disease.
Factors That Increase Demand For Selenium
You may need more selenium if you’re:
- older,
- alcohol-dependent,
- hypothyroid,
- Immune compromised,
- diagnosed with HIV/AIDS,
- on dialysis,
- dealing with kidney failure,
- live in a region where selenium is low in the soil,
- following a plant-based diet,
- taking corticosteroids for a long time,
- experiencing premenstrual tension (PMS), or
- pregnant.
Satiety Response to High Selenium Foods
Our satiety analysis indicates that foods containing more selenium tend to provide greater satiety up to around 400 mcg/2000 calories. People who consume more selenium per calorie tend to eat up to 26% fewer calories than people who consume the least selenium.
The average selenium intake for Optimisers was 185 mcg per 2000 calories with an 85th percentile value of 300 mcg per 2000 calories.
This is significantly greater than the Estimated Average Requirement of 50 mcg per day and the Recommended Daily Intake of 70 mcg per day for men. In addition, the recommended minimum intake of selenium for pregnant women remains set at only 60 mcg/day and 70 mcg/day for breastfeeding women.
Selenium Toxicity
Although selenium is required for health, high doses of selenium can be toxic and even fatal. To avoid toxicity, an Upper Intake Level of supplemental selenium has been set at 400 mcg/day.
If you’re getting too much selenium in your diet, you might experience GI upset, hair loss, nausea, breath that smells like garlic, a metallic taste, skin rashes, lesions, fatigue, irritability, and muscle tenderness.
Although selenium toxicity is often achieved by taking supplemental selenium, eating too many selenium-rich foods like Brazil nuts too frequently can result in toxicity, too. More is not always better!
Selenium Stretch Target
Our satiety analysis recommends a stretch target of 300 mcg/day for men and 240 mcg/day for women.
nutrient | men | women |
selenium (mcg) | 300 | 240 |
Availability of Selenium in the Food System
Selenium content depends on the selenium content of the soil that the food is grown in.
In certain parts of China, where large proportions of the population are vegetarian and soil selenium levels are low, inhabitants have one of the most inadequate selenium intakes. These selenium-deficient areas correspond to a 69% higher risk of thyroid disease. Average selenium intakes are also low in some European countries. The risk for deficiency increases significantly in populations following a vegan diet.
The selenium content of foods generally available will provide you with enough of this mineral to meet the Recommended Daily Intake of 44 mcg/day. However, you will still need to prioritise nutrient-dense foods to meet more optimal levels. As we can see in the chart below, selenium content in our food system declined over the past century until selenium fortification ramped up in the mid-1970s (data from USDA Economic Research Service).
Synergistic Nutrients
Selenium is not a one-person show. Instead, it works synergistically (or together) with vitamins B3, C, E, cysteine, glutathione, methionine, zinc, and iodine.
For this reason, it’s best to eat foods containing selenium because they often have a complete vitamin and mineral profile. In contrast, supplements are usually in isolated form.
The Nutrient Profile of High Selenium Foods
The nutrient fingerprint chart below shows that we can obtain plenty of selenium from a nutrient-dense diet.
Because selenium is found most abundantly in seafood and animal foods, a diet with more selenium will have a significant amount of protein and carbs than fat.
How Can I Calculate my Selenium Intake?
If you’re interested in checking if you’re getting enough selenium in your diet, you can observe your nutrient profile using our Free 7-Day Nutrient Clarity Challenge.
After a week of tracking your current diet in Cronometer, Nutrient Optimiser will give you a prioritised list of foods and NutriBooster recipes that will help you plug your current nutritional gaps.
Level Up Your Nutrient Density
To help you level up your nutrient density, we’ve prepared a Nutritional Optimisation Starter Pack to ensure you are getting plenty of all the essential nutrients from the food you eat every day.
The free starter pack includes:
- Maximum Nutrient Density Food List
- Sample Maximum Nutrient Density Recipe Book
- Sample Maximum Nutrient Density Meal Plan.
To get started today, all you have to do is join our new Optimising Nutrition Group here.
Once you join, you will find the Nutritional Optimisation starter pack in the discovery section here.
Nutrient Density Index
Minerals
Vitamins
- Vitamin A
- Vitamin E
- Thiamine (B1)
- Riboflavin (B2)
- Niacin (B3)
- Pantothenic acid (B5)
- Vitamin B6
- Folate (B9)
- Vitamin B12
- Vitamin C
- Vitamin D
- Choline
- Vitamin K1