As a clotting factor, fibrinogen is essential for the body’s healing processes. However, high levels can be harmful to your health. Read on to understand the hidden causes and risks of high levels and how to lower fibrinogen naturally.
Hidden Causes of High Fibrinogen Levels
Multiple studies (9,127 participants; 200 participants; 11,059 participants) have found that smokers and ex-smokers have significantly higher fibrinogen levels than non-smokers (up to 53% more fibrinogen, and up to 11% more, respectively) [9, 10, 11].
Smoking more seems to further increase fibrinogen, and fibrinogen levels do not return to normal until a person has refrained from smoking for 15 years (11,059 participants; 118 participants) [11, 12].
4) Birth Control
Estrogen may elevate fibrinogen by increasing the expression of the FGG gene and production of the protein, as seen in rats .
As shown in a study with 194 participants, this effect was compounded in women who smoked while on birth control .
5) Genetic Mutations
Multiple studies (895 participants; 1,002 participants; 7,329 participants) estimated that genes account for 34 to 46% of the variation in fibrinogen levels. A number of mutations associated with high fibrinogen levels are discussed below [19, 20, 21].
The inherited disorder homocystinuria increased blood levels of the amino acid homocysteine (3,216 participants), which lab experiments suggest may inhibit the breakdown of fibrinogen, leading to elevated levels [22, 23, 24].
Multiple studies (9,127 participants; 72 participants; 12 participants; 3,967 participants) have found that older people tend to have higher levels of blood fibrinogen, with concentrations increasing around 0.1 – 0.2 g/L each decade [9, 25, R, 26].
7) Cold Temperatures
Cold temperatures increase fibrinogen levels, resulting in chronic elevation during the winter months (2-hour study with 12 participants; yearlong study of 1,002 participants; yearlong study of 24 participants) [27, 28, 29, 30].
Elevated fibrinogen of 206 Japanese emigrants in Hawaii was associated with more iron and sugar consumption. This could implicate the prevalence of meat and high glycemic foods in the Western diet, which is also associated with cardiovascular disease .
A survey of 1,854 people found that high fibrinogen was associated with low blood concentrations of minerals and vitamins, such as iron and vitamin B6, as well as high levels of cholesterol and fatty acids. This suggests that both under- and overnutrition can increase fibrinogen .
A study of 16 individuals also found that fibrinogen increased by 20 to 40% directly after the participants drank a protein shake or balanced-meal shake, but not after drinking water .
Health Risks of Elevated Fibrinogen
1) Promotes Inflammation
Fibrinogen activates molecules that increase inflammation (IL-8, MCP-1, MMP-9, Mac-1) while inhibiting molecules that would decrease it (PPARα, PPARγ), both in the blood and the brain [36, 37, 38, 39].
Certain types of bacteria (Streptococcus) bind to fibrinogen in order to promote inflammation during infection .
Therefore, therapies to decrease fibrinogen/white blood cell binding may improve symptoms of common inflammatory diseases like rheumatoid arthritis, multiple sclerosis, and bacterial infection [40, 43, 44, 45].
2) Increases the Risk of Harmful Blood Clots
High fibrinogen is associated with higher rates of heart disease, blood vessel dysfunction, and stroke. By some estimates, high fibrinogen predicts these diseases as well as high blood pressure and smoking [46, 47, 48, 49].
In a study of 1,363 patients, high fibrinogen levels were also associated with a greater risk of developing heart disease within 18 months .
Furthermore, a longitudinal study of 158 participants concluded that people with larger fibrinogen spikes due to stress had poor blood vessel health, and therefore a greater risk of heart disease 3 years down the road .
Fibrinogen and its degradation by-products were also found in the plaque and cholesterol that builds up on the walls of blood vessels and can cause blockage .
3) May Harm the Brain
Fibrinogen may increase brain deterioration in Alzheimer’s disease. Lab and rat experiments found that by binding to the abnormal brain plaque, fibrinogen increased damage to brain cells and blood vessels, while also promoting inflammation [59, 60, 61, 62].
Fibrinogen also suppressed the brain’s ability to heal itself in lab experiments. It did this by inhibiting the regeneration of brain cells and the protective myelin sheaths that normally cover them [64, 65].
4) Associated with Diabetes
In a case-control study, 6 diabetic patients had high levels of both fibrinogen and glucagon, the hormone responsible for increasing blood sugar, but normal levels of albumin, a marker of insulin resistance. In other words, elevated fibrinogen may precede and possibly contribute to the development of diabetes [70, 71].
5) May Promote Cancerous Tumors
6) Associated with High Blood Pressure
A study of 143 people over 3 years found that increased fibrinogen after a stressful task predicted the later development of high blood pressure. People with stable fibrinogen levels did not develop high blood pressure. For unknown reasons, this effect was found exclusively in women .
Most of the causal relationships between fibrinogen concentration and associated diseases remain unclear. More research is needed to make concrete conclusions about the effects of and effects on fibrinogen.
How to Lower Fibrinogen Levels
1) Cholesterol Medication and Diet
A meta-analysis of 22 trials and 2,762 participants found that fibrate cholesterol medication most effectively reduces fibrinogen compared to statins .
Foods that improve bad (LDL) cholesterol may also decrease fibrinogen levels, such as healthy fats and dietary fiber .
2) Drugs That Slow Blood Clotting
3) Fish Oil
A double-blind cross-over study of 20 participants found that 6 grams per day of fish oil reduced fibrinogen by 20% after 6 weeks .
Another study of 25 participants found that three grams per day of fish oil for 4 weeks reduced fibrinogen blood levels by 3% on average .
It seems that strenuous exercise, in particular, reduces fibrinogen: 2 studies of 156 (ten weeks) and 8 participants (one week) showed that fibrinogen decreased by 10 to 20% after intense workouts [92, 93].
Turmeric, a known remedy for inflammation and heart disease, decreased blood fibrinogen levels in a study of 30 subjects. Fibrinogen can also bind to curcumin (the active ingredient in turmeric) so that it does not degrade as quickly in the bloodstream [94, 95].
6) Traditional Chinese Medicine
The traditional Chinese medicines Quyu Jiedu, Xuebijing treatment, and XueFu ZhuYu decoction, reduced blood fibrinogen levels in 2 meta-analysis studies (15 RCTs with 1,364 patients; 11 RCTs with 686 patients) evaluating the use of traditional Chinese medicine for high blood pressure and chest pain from heart disease [96, 97].
7) Moderate Alcohol Consumption
Multiple studies (117 participants for 1 month; 20 participants for 6 weeks; 11 participants for 12 weeks) have shown that daily moderate alcohol consumption (wine or beer) reduced blood fibrinogen levels [98, 99, 100].
A glass of red wine a day for 40 days was seen to decrease blood fibrinogen levels by 8 to 15% in a clinical trial of 69 healthy adults .
8) Olive Oil
9) Nattokinase (Fermented Soybean)
10) Hormone Replacement Therapy
Multiple studies (trial of 152 women for 1 year; 29 women for 6 months; surveys of over 5k women) have found that hormone replacement therapy may help reduce fibrinogen levels in postmenopausal women, though the effect appears to be minimal [103, 104, 105, 106].
12) B Vitamins
A study of 24 adults found that 5 mg/day of vitamin B9 for 4 weeks reduced blood fibrinogen levels by an average of 9% .
A 4-week regime of vitamin B6, B9, and B12 also reduced blood fibrinogen levels in 21 patients with sepsis .
- Causes & Risks of Low Fibrinogen + How to Increase Levels
- What Is Fibrinogen? Function, Test & Normal Levels
Irregular Fibrinogen Levels?
LabTestAnalyzer helps you make sense of your lab results. It informs you which labs are not in the optimal range and gives you guidance about how to get them to optimal. It also allows you to track your labs over time. No need to do thousands of hours of research on what to make of your lab tests.
LabTestAnalyzer is a sister company of SelfHacked. The proceeds from your purchase of this product are reinvested into our research and development, in order to serve you better. Thank you for your support.
Several lifestyle factors can increase your fibrinogen levels, including smoking, cold temperatures, eating a meat-heavy or high-carb diet, and vitamin B6 and iron deficiency. Women on birth control pills and people who are overweight also tend to have higher levels.
Fibrinogen levels normally rise in pregnancy and with aging. Additionally, people with genetic variants that increase homocysteine are more likely to have high fibrinogen levels.
Your body requires some fibrinogen for optimal health, but high levels can be harmful. If your fibrinogen levels rise too much, you will be at an increased risk of inflammation, heart disease, high cholesterol, diabetes, and dementia.
To lower your levels naturally, exercise on a regular basis and increase your dietary intake of olive oil, fish oil, and fiber. Vitamin B, turmeric, and nattokinase supplements may also help. If your fibrinogen levels are very high, your doctor may also prescribe fibrate or anti-platelet medication.