Flaxseed oil, derived from the seeds of the flax plant (Linum usitatissimum), is a widely used dietary supplement. It is a plant-based source of alpha-linolenic acid (ALA), an omega-3 fatty acid. Your body cannot produce ALA, making it an essential nutrient that must be obtained through diet or supplementation. The oil is extracted by grinding and pressing flax seeds.
General Dosage Guidelines
For healthy adults, a typical daily intake of flaxseed oil for overall wellness is 1 to 2 tablespoons of liquid oil. This amount can help meet or exceed the recommended daily ALA intake, which is approximately 1,600 milligrams for men and 1,100 milligrams for women. One tablespoon of flaxseed oil contains close to 7,000 milligrams of ALA.
When considering flaxseed oil in capsule form, the equivalent dosage can vary based on the manufacturer and the ALA content per capsule. Many studies have utilized doses of 1,000 milligrams of flaxseed oil. Manufacturers may suggest one to three capsules per day, depending on the concentration of ALA in each capsule. There is no single official Recommended Dietary Allowance (RDA) for ALA, so these are common guidelines based on adequate intake levels.
Dosage for Specific Health Goals
For Constipation
Flaxseed oil has been explored for its potential laxative properties. A 2015 study involving hemodialysis patients experiencing constipation used flaxseed oil at an initial dose of 4 milliliters (mL) per day. The study found that flaxseed oil, along with olive oil, was effective in improving stool consistency and frequency of bowel movements. While flaxseed oil can be beneficial, ground flaxseed, which contains fiber, is often highlighted for constipation relief as fiber contributes directly to stool bulk and softness.
For Heart Health
Research has investigated various dosages of flaxseed oil for its effects on heart health, particularly concerning blood pressure and cholesterol levels. One study involving 59 participants showed that supplementing with one tablespoon (15 mL) of flaxseed oil daily for 12 weeks led to significantly lower blood pressure compared to safflower oil. Other studies indicate that dosages of 8 grams of ALA per day for dyslipidemic men or 20 grams per day of flax oil for obese adults with insulin resistance markers resulted in decreased systolic, diastolic, and mean arterial blood pressure.
Regarding cholesterol, several studies have observed that daily flaxseed intake can lower total cholesterol and low-density lipoprotein (LDL) cholesterol. A 2015 study found that taking ALA-rich flaxseed oil for 12 weeks lowered small-dense LDL cholesterol particles in men. These benefits are attributed to the high concentration of omega-3 fatty acids in flaxseed oil, which can increase omega-3 levels in the blood. Before using flaxseed oil for therapeutic purposes, it is always advisable to consult a healthcare provider.
For Inflammation
Flaxseed oil’s omega-3 fatty acid content has led to investigations into its anti-inflammatory effects. A 2018 meta-analysis of studies involving individuals with metabolic syndrome found that flaxseed oil supplementation reduced markers of inflammation such as inflammatory cytokines. Another meta-analysis of 12 studies indicated that flaxseed oil decreased inflammatory markers like interleukin-6 (IL-6) and malondialdehyde (MDA).
While some studies suggest a reduction in C-reactive protein (CRP), an inflammation marker, particularly in individuals with obesity, results have been mixed in other populations. Dosages in these studies varied, with some using 1,000 milligrams of flaxseed oil twice daily for 12 weeks. More research is underway to fully understand flaxseed oil’s effects on inflammation in the general population and at different dosages.
Factors That Influence Dosage
An individual’s dietary habits can influence their flaxseed oil dosage needs. Those who consume other sources of omega-3 fatty acids, such as fatty fish, may require less flaxseed oil supplementation. For vegetarians and vegans, flaxseed oil can be a good way to ensure adequate omega-3 intake, as fish is a common source of these fats.
Body weight can also play a role, with some studies showing more pronounced effects of flaxseed oil on inflammatory markers in individuals with higher body mass index. Age is another consideration, though ALA absorption and metabolism from flaxseed oil may not be affected by age. For children, established safe dosages are not available, and medical consultation is necessary before administering flaxseed oil to them.
Signs of Taking Too Much
Exceeding recommended dosages of flaxseed oil can lead to several adverse effects, primarily affecting the gastrointestinal system. Common side effects include loose stools and diarrhea, which can occur with doses of 30 grams (approximately two tablespoons) or higher per day. Other digestive discomforts like bloating and gas may arise.
Flaxseed oil also possesses blood-thinning properties, as its omega-3 fatty acids can interfere with the blood’s ability to clot. This effect makes caution necessary for individuals taking anticoagulant or antiplatelet medications, as combining them with flaxseed oil could heighten the risk of bruising and bleeding. It is recommended to discontinue flaxseed oil supplementation at least a few weeks prior to any scheduled surgery to prevent bleeding complications.