Phosphorus is the second most abundant mineral in the body, essential for energy use, bone, heart, lung, and brain health. Imbalances may disrupt your metabolism and raise your risk of chronic diseases. Diet and income can have a huge impact, affecting the amount of dangerous phosphate additives in your grocery basket. Learn more about the causes and effects of abnormal blood phosphate and how to naturally optimize it.
What is Phosphorus?
Phosphorus is the sixth most abundant element in the body after oxygen, hydrogen, carbon, nitrogen, and calcium. It is the second most abundant mineral and makes makes up about 1% of our body weight [R, R].
Phosphorus is mainly found as phosphate in the body. The terms phosphate and phosphorus are often used interchangeably, although they don’t have the same meaning [R, R]. Phosphorus is an atom, while phosphate is made when phosphorus is bound to oxygen (4 oxygen atoms).
Phosphorus has many important roles [R]:
- Helps build cells, DNA, and proteins
- Crucial for strong bones and teeth
- Vital for energy metabolism, as the “P” of ATP — the “energy currency” of our cells
- Required for muscle contractions and sending out nerve signals
- As the most abundant anion (negative ion) in the body, phosphate helps maintain the acid-base balance (pH)
Blood phosphate comprises a very small part of total body phosphate. Nevertheless, it gives a good estimate of phosphate levels in the body [R].
Phosphorus in the Diet: The Role of Processed Food
A regular Western diet provides between 1000 and 2000 mg/day of phosphorus. The average intake of a U.S. adult is around 1400 mg/day, double the recommended dietary allowance (RDA) of 700 mg/day [R, R, R].
It turns out that the amount of total dietary phosphate is directly influenced by the intake of processed food and beverages. However, this is not due to naturally high phosphorus in these food items. Instead, it’s a result of phosphate salts being used as additives [R].
Manufacturers add phosphates to their products to enhance appearance and shelf life. Phosphorus-based additives are used as pH stabilizers, leavening, and anti-bacterial agents. They account for about 10–50% of total daily phosphorus intake in the typical Westernized diet [R, R].
One study looked into over 2000 best-selling grocery products in Ohio. 44% of them contained phosphate additives. The additives were particularly common in:
- Prepared frozen foods (72%)
- Dry food mixes (70%)
- Packaged meat (65%)
- Bread & baked goods (57%)
- Soups (54%)
- Yogurt (51%)
People who consume meals comprised mostly of phosphorus-additive-containing foods take in 736 mg more phosphorus per day than people who mostly consume additive-free foods. However, “additive-enhanced” food items cost $2 less per day than additive-free meals [R].
In a study of over 7.8k people, milk and dairy products with phosphate additives greatly increased blood phosphorus levels (0.07 mg/dL for each additional serving). Additive-containing cereal and grain products had a similar effect (0.005-mg/dL increase for each additional serving) [R].
Several studies have associated high phosphorus intake or high blood phosphate levels with increased mortality and chronic diseases, including heart disease and cancer [R].
Natural or organic sources of phosphorus need to be broken down by digestive enzymes, leading to slower and less efficient absorption in the gut. The absorption ranges from 40 to 70% and is higher from animal sources (up to 70%) than from plants (up to 50%). Phytates greatly lower phosphorus bioavailability, such as in whole grains and vegetables [R, R, R].
In a non-fortified mixed diet, most of the digestible phosphorus comes from proteins, making protein-rich foods the main source of natural phosphorus [R].
Phosphorus is absorbed in the gut, stored in the bones, and removed by the kidneys.
Phosphate in the bones acts as a buffer that responds to specific imbalances. It moves in and out of bones as needed. Bone breakdown releases phosphorus, raising its blood levels. Increased bone mineralization, on the other hand, attracts phosphorus into the bones and lowers its blood levels [R, R].
In the adults, kidneys will normally get rid of a fairly constant amount of phosphorus (> 90%). But when the supply is low, kidneys can reabsorb phosphate very efficiently, reducing urine levels down to virtually zero. Also, when there’s phosphate overload, healthy kidneys can rid the body of any excess amounts [R, R].
- Calcitriol, or active vitamin D: promotes phosphorus absorption in the gut and increases blood phosphate levels
- Parathyroid hormone: increases kidney excretion of phosphate and lowers blood phosphate levels
- FGF23: increases kidney excretion of phosphate and decreases its gut absorption, reducing blood levels
Phosphorus metabolism is tightly bound to that of calcium — both minerals are affected by the same hormones, usually in opposite direction. In addition, phosphate can bind calcium in the blood, thereby reducing its levels. Our health depends on a delicate balance between these two minerals [R, R].
You can measure your phosphate levels by doing a simple blood test.
Newborns have the highest phosphate levels (4.0 – 8.0 mg/dL) as they require more of this mineral for bone growth and soft tissue development. Levels in children are around 3.0-6.0 mg/dL, and continue to gradually drop toward adulthood [R].
Accordingly, phosphate absorption and reabsorption (in the gut and kidneys, respectively) decline with age [R].
In adults, the normal range is between 2.5 and 4.5 mg/dL (milligrams per deciliter). That equals roughly 0.8 – 1.45 mmol/L (millimoles per liter).
- Time of the day — levels are lowest in the morning and highest in the evening
- Season — higher in the summer than winter
- Gender — male children and adolescents have slightly higher levels
- Genetics — some genetic mutations affect phosphate absorption in the gut and reabsorption in the kidneys
Low Phosphorus (Hypophosphatemia)
Low phosphate levels in the blood are called hypophosphatemia (“hypo” = low, “phosphatemia” = blood phosphorus). You may have low phosphate levels without noticing, because symptoms and signs do not appear until the deficiency becomes serious.
There are 3 main mechanisms that decrease phosphate levels: (1) inadequate phosphate intake and/or absorption, (2) increased kidney excretion, and (3) increased cell and tissue needs [R].
Phosphate deficiency is linked to various conditions, some of which impact only absorption, while others can affect more than one mechanism.
Nutrition- or gut-related disorders
- Long-term malnutrition and shortly upon replenishment (the so-called “refeeding syndrome”), when phosphorus-depleted cells syphon all available free phosphate from the blood [R, R]
- Anorexia [R]
- Potassium or vitamin D deficiency [R]
- Poor absorption (malabsorption) [R, R]
- Chronic diarrhea, which also lowers gut phosphate absorption [R, R]
- Hyperparathyroidism, or high parathyroid hormone levels, which leads to a greater loss of phosphate via kidneys [R, R]
- Hungry bone syndrome, which occurs after correcting for hyperparathyroidism and results in an increased bone demand for phosphorus [R]
- Hypothyroidism [R, R]
Acid-base and/or metabolic disorders
- Respiratory alkalosis (due to hyperventilation or overbreathing), which occurs when carbon dioxide blood levels drop, causing blood pH to rise and become too alkaline [R, R]
- Panic disorder, as overbreathing can cause respiratory alkalosis and decrease blood phosphate [R, R]
- Gout [R]
- Poorly controlled diabetes. Glucose in the urine (glycosuria) increases phosphate loss through urine [R]
- Treatment for diabetic ketoacidosis [R]
- Alcoholism [R, R]
- Heat stroke, hyperthermia, and fever [R, R, R]
- Severe burns [R, R]
- Severe infection (including sepsis, Legionnaires’ disease, and other respiratory infections) [R]
- Fanconi’s syndrome, a kidney disorder that results in excess urine production [R]
- Softening of the bones from cancer (oncogenic osteomalacia) [R]
- Genetic disorders, such as X-linked hypophosphatemic rickets [R, R]
- Antacids, such as aluminum or magnesium antacids (e.g. Tums). These bind to phosphate in the gut.
- Diuretics such as acetazolamide (Diamox, Diacarb), hydrochlorothiazide (Microzide, HydroDiuril), indapamide (Lozol), and furosemide (Lasix)
- Theophylline, used to treat asthma and COPD
- Bronchodilators and corticosteroids, also often used to treat asthma
- Bisphosphonates, used to treat osteoporosis
- Insulin therapy
- Mannitol therapy, used to reduce high pressure in the brain (from injuries, surgery, or tumors)
- Estrogens such as mestranol (Enovid, Norinyl, and Ortho-Novum), used in many birth control pills
- Phenytoin (Dilantin) and phenobarbital (Luminal), used to treat seizures
- Antiviral acyclovir (Zovirax)
- Imatinib mesylate (Gleevec, Glivec) and cisplatin (Platinol), used as chemotherapy drugs
Symptoms and Signs
Most people with low phosphate levels are without symptoms. If you have mild hypophosphatemia, you may experience mild to moderate weakness in your body [R].
- Loss of appetite
- Anemia (due to hemolysis, or the destruction of red blood cells)
- Muscle weakness
- Irregular breathing
- Burning or prickling sensation in various parts of the body (paresthesia)
- Impaired coordination, balance and speech (Ataxia)
- Irregular heartbeat (arrhythmia)
- Heart failure
- Bone pain and fractures
1) Low Phosphate Weakens the Bones
Bones are continually being remodeled, undergoing a balanced breakdown and re-building (mineralization). In fact, most of the adult skeleton is completely replaced every 10 years or so [R].
Without sufficient phosphate, bone mineralization can come to a halt [R].
- Low bone mineral density (Osteopenia)
- Brittle bones (Osteoporosis)
- Softening of the bones (Osteomalacia)
- Rickets, a disease that weakens the bones in children
2) Low Phosphate Causes Muscle Weakness
Low phosphate can lead to muscle weakness, which can impact the heart muscle and the muscles needed for breathing.
3) Low Phosphate Levels Increase the Risk of Heart Disease
In a large study of over 110k people, extreme blood phosphate levels — either too high or too low — increased the risk of heart disease (a so-called “U-shaped” relationship). But the deficiency does not need to be severe, even lower levels within the normal range increased the risk [R].
4) Low Phosphate Levels Impair Lung Function
Muscles of the diaphragm and rib cage allow us to breathe. Phosphate deficiency weakens these muscles and can lead to an inability to breathe (respiratory insufficiency). Although common in people with phosphate deficiency, this condition improves with phosphate repletion [R+, R].
5) Low Phosphate Levels Can Cause Anemia
6) Low Phosphate Levels Impair the Brain
- A sensation of tingling and numbness (paresthesia)
- Altered mental states
- Auditory and visual hallucinations
- Paranoid delusions
- Slurred speech
- Nerve pain
7) Low Phosphate Levels are Linked With Alzheimer’s Disease
In 109 people with mild cognitive impairment and 73 people with Alzheimer’s, those with lower blood phosphate levels had more beta-amyloid plaque buildup in the brain [R]. These plaques are the hallmark of Alzheimer’s disease.
In another study of 94 people, those with Alzheimer’s had lower blood phosphate than either the controls or patients with non-Alzheimer’s dementia [R].
8) Low Phosphate Levels are Linked to Obesity
A study of over 46k people found a link between lower blood phosphate levels and higher BMI [R].
Lower phosphate levels were associated with obesity in both women and men in another study of almost 2k people [R].
Similarly, in a study of 298 children and adolescents, those who were obese had much lower blood phosphate levels [R].
9) Low Phosphate Levels Are Associated with Insulin Resistance
Further, lower phosphate levels were associated with higher insulin resistance (HOMA-IR) in a study of 190 obese children and adolescents [R].
10) Low Phosphate Levels Are Associated with High Blood Pressure
In over 46k people, lower blood phosphate levels were linked with higher blood pressure (systolic and diastolic) [R].
In another study of 79 men, those with high blood pressure had lower phosphate levels than those who were healthy. What’s more, lower blood phosphate predicted higher blood pressure 20 years later in a study in 56 men [R, R].
11) Low Phosphate Levels are Associated with Metabolic Syndrome
Metabolic syndrome increases your risk of heart disease, stroke, and diabetes [R].
You have metabolic syndrome if you have any 3 of the following [R]:
- High blood pressure
- High blood sugar
- Excess body fat around the waist
- Low HDL cholesterol
- High triglyceride levels
In over 46k people, lower blood phosphate levels were linked with lower HDL cholesterol and higher BMI, fasting glucose, insulin, insulin resistance (HOMA-IR), triglyceride levels, blood pressure, and waist circumference. People with low phosphate were also more likely to suffer from chronic inflammation, measured by hs-CRP [R].
In 56 men, those with the lowest phosphate levels at baseline had the highest number of risk factors associated with metabolic syndrome 20 years later [R].
12) Low Phosphate Levels Can Cause Metabolic Acidosis
Metabolic acidosis is a condition that occurs when the body produces excessive quantities of acid or when the kidneys are not removing enough acid from the body. Both scenarios can be triggered by low phosphate levels [R, R].
13) Low Phosphate Levels May Increase Mortality
In over 42k hospitalized patients, those with blood phosphate levels in the extreme range (high or low) were at a greater risk of dying. Low phosphate levels increased the risk by 1.6 times [R].
In over 3.2k kidney disease patients on dialysis, low phosphate levels were associated with dying (from any cause or infection) [R].
Ways to Increase Blood Phosphorus
Eat more phosphate-rich dietary sources such as dairy, grains, meat, and fish [R].
Make sure to correct any nutritional deficiencies that can decrease your phosphate levels:
- If deficient in potassium, increase potassium-rich foods in your diet, such as potatoes, sweet potatoes, winter squash, bananas, and citruses/orange juice.
- If your vitamin D is low, consume more fatty fish (like tuna, mackerel, and salmon), beef liver, cheese, and egg yolks. Spend more time outdoors in the sun to boost your vitamin D levels.
Quitting alcohol after chronic abuse can rapidly improve phosphate levels [R].
If your drugs lowering your phosphorus levels, discuss alternative options with your doctor [R].
If you suffer from anxiety, pay attention to your breathing. When you panic, you tend to breathe fast and shallow — in other words, you hyperventilate. This triggers a set of reactions in your body that decrease blood phosphate levels [R]. If you are prone to anxiety, engage in activities that promote deep and slow breathing, such as breathing exercises, meditation, or yoga.
In mild hypophosphatemia, your doctor may prescribe phosphate supplements. In severe and symptomatic cases, intravenous phosphate may be needed [R].
Supplements that can help:
High Phosphorus (Hyperphosphatemia)
High blood phosphate levels are called hyperphosphatemia (“hype”r = high, “phosphatemia” = blood phosphorus). The bad news is that high phosphorus increases your risk of various diseases and mortality. The good news is that you can lower your phosphate levels by applying simple modifications to your diet and your lifestyle.
These increase blood phosphate levels:
- Kidney disease/failure — impaired kidney function is the most common cause of high blood phosphate levels [R]
- Too much vitamin D [R]
- Milk-alkali syndrome, caused by calcium overdosing [R, R]
- Increased dietary intake of phosphorus-containing foods (phosphate supplementation, soft drinks and pre-packaged food) [R, R]
- Prolonged exercise [R, R, R, R]
- Dehydration [R]
- Smoking [R, R]
- Low parathyroid hormone levels (hypoparathyroidism) [R]
- Overactive thyroid gland (hyperthyroidism) [R]
- Rhabdomyolysis, where phosphorus “leaks” from damaged muscles into the blood [R, R, R]
- Rupture of red blood cells (hemolysis) [R, R]
- Diabetic ketoacidosis, a serious life-threatening complication of diabetes [R]
- Acromegaly, caused by too much growth hormone [R]
- Cancer [R]
- Tumor lysis syndrome [R, R]
Using phosphate-containing laxatives can also increase your phosphate levels [R].
The following can interfere with phosphate measurement, resulting in falsely high levels:
High Blood Phosphate and Poverty
Two studies have linked high blood phosphate with poverty.
In the first study of 14k US adults, participants with income below the poverty level were twice as likely to have high blood phosphate levels (≥ 4.4 mg/dL) [R].
Similarly, in the second study with over 2.8k people, those who had the lowest income or were unemployed were more than twice as likely to have high phosphate levels [R].
This relationship is probably a direct consequence of diet. People who are poor and live in urban environments consume cheaper processed and fast foods that contain phosphate additives [R].
Symptoms and Signs
If you have mild hyperphosphatemia, you probably won’t experience any symptoms.
- Muscle cramps and spasms (tetany)
- Bone weakness
- Chalk-like calcium deposits (calcification) in tissues. Deposits within the walls of blood vessels can lead to a hardening of the arteries.
- Severe itching
Severe complications include [R]:
- High resting heart rate (tachycardia)
- Low blood pressure (hypotension)
- Heart attack
1) High Phosphate Levels Increase the Risk of Heart Disease
High phosphate binds calcium and forms crystals (calcium phosphate) that can accumulate in various tissues. In the blood vessels, their buildup (calcification) may cause damage or hardening [R, R, R].
In a large study of over 110k people, both low and high blood phosphate levels were linked to an increased risk of heart disease. Higher levels within the normal range also increased the risk [R].
In another study of over 2.5k people, higher-range normal levels (>3.6 mg/dL) were linked to a 1.5X higher risk of calcification in the arteries, while levels above 4 mg/dL increased the risk by over 2X [R].
High levels are linked to both heart risks in healthy people and heart complications in those with heart disease. In over 3k healthy people, each 1 mg/dL increase in phosphate levels raised the risk of heart disease by 1.3X. In over 4k people with heart disease, higher levels were linked with a greater risk of heart failure and heart attacks [R, R].
2) High Phosphate Levels Increase the Risk of Chronic Kidney Disease
In a study of over 2k healthy people, those with phosphorus above 4 mg/dL had double the risk of developing chronic kidney disease [R].
3) High Phosphate Levels Increase the Risk of Fractures
In over 12k people, higher blood phosphorus levels, even within the normal range, were linked with increased fracture risk in both men and women [R].
Many other studies looked at this relationship by focusing on dietary phosphate intake instead of the blood levels. As dietary phosphate intake increases, bones are broken down more and rebuilt less [R, R, R, R].
Strong bones require a balance between phosphorus and calcium levels. High dietary phosphorus can throw this balance off. In 85 postmenopausal women, consumption of one or more bottles per day of phosphoric acid-containing soft drinks (such as coke) was associated with low calcium levels [R].
4) Higher Phosphate Levels and Poor Cognitive Function
In a study of over 5.5k men, higher baseline blood phosphate was associated with higher odds of poor executive function 4 years later [R].
High phosphate levels may weaken the blood-brain barrier, which can have a major effect on brain function. In a study of 186 people, phosphate levels > 3.9 mg/dL were linked with 3.7 higher odds of brain lesions, likely resulting from a weakened blood-brain barrier [R].
5) High Phosphate Levels May Increase the Risk of Infections
In over 1000 dialysis patients, infections were more frequent among those with high phosphate levels [R].
6) High Phosphate Levels May Accelerate Aging
Animals studies show that high phosphate levels can accelerate the aging process by triggering tissue damage. In mice, high phosphate caused premature aging symptoms such as weight loss, spine deformities, decreased the production of sex hormones, infertility, muscle wasting, skin thinning, and reduced life span [R].
In over 7k people, higher phosphate levels were linked to an age-related decrease in muscle strength in those over 65 years old [R].
7) High Phosphate Levels May Increase the Risk of Cancer
The relationship between high phosphate levels and cancer risk is not straightforward. High phosphate levels are mostly linked to an increased risk of cancer, but they may also decrease the risk in some cases. High levels may be more detrimental for men than for women, although this is still uncertain.
In almost 400k people, higher phosphate levels were linked to higher overall cancer risk in men. High levels increased the risk of pancreatic, lung, thyroid, and bone cancer in men, and esophagus, lung, and nonmelanoma skin cancer in women. Conversely, the risk of breast, endometrial, and other endocrine cancers dropped with higher phosphate levels in both sexes [R].
In over 47k men, higher dietary phosphorus was associated with greater risk of total, deadly, and high-grade prostate cancer [R].
In a small study of 100 people, all cancer patients had high phosphate levels [R].
Feeding mice with a diet high in phosphate stimulates the growth of lung tumors, both in number and size [R].
8) High Phosphate Levels Increase Mortality
In a study of almost 13k people, high blood phosphate levels were linked to increased mortality [R].
In over 42k hospitalized patients, phosphate levels on either end of the extreme range (high or low) were linked to in-hospital deaths. Low levels increased the risk by 1.6 times, while high levels increased the risk by up to almost 4 times. In a smaller study on 4k people with heart disease, blood phosphate over 3.5 mg/dL increased the risk of death by 1.3 times [R, R].
In almost 1k people, baseline phosphorus >3.9 mg/dL increased the risk of death from heart disease over the next 5 years [R].
Some studies found that this link holds true only in men. In 6k people monitored for over 10 years, phosphate was linked to deaths only in men. Higher phosphate in men increased the risk of heart disease-related deaths by 1.7X, chronic lung disease deaths by 1.9X, and deaths from chronic obstructive pulmonary disease by 4.4X [R].
In another study on over 1.3k older men, higher phosphorus levels (≥3.6 mg/dL) increased the risk of death from any cause by 1.6 times. In an 18-year follow-up study of over 2.5k people with high blood pressure, diabetes, and/or obesity, higher phosphate levels were associated with more deaths in men [R, R].
Phosphorus intake alone may increase the risk regardless of blood levels. In over 9.6k healthy adults, higher phosphorus intake was associated with higher deaths from any cause in those who consumed >1400 mg/day of phosphorus [R].
Decreasing phosphorus levels may lower the risk. In over 6.7k patients with chronic kidney disease on dialysis, phosphate-binding agents decreased the deaths from heart disease or other causes by over 20% [R].
Ways to Decrease Blood Phosphorus
Eat foods that are low in phosphorus to maintain blood phosphate levels within a healthy range. Avoid protein-heavy and dairy products. Most importantly, eliminate foods that contain phosphate additives (cooked ham, roast breast turkey/chicken) and soft drinks [R, R].
Avoid night-time snacks! In a study of 14 healthy men, night-time snacking increased baseline blood phosphorus levels, by reducing phosphorus flushing via the kidneys [R].
Make sure you are properly hydrated [R].
Avoid using enemas that contain phosphate salts. Your body can absorb these salts, leading to excess phosphate levels in the blood [R].
If you have uncontrolled diabetes, it is critical to bring it under control with diet, exercise, and prescribed therapy [R].
If your phosphate levels high, your doctor will usually prescribe fluids (unless you have kidney failure). If your levels have been high for a long time, phosphate binders such as aluminum and magnesium salts can reduce the phosphate load. These do have side effects and can only be used in a limited capacity [R].
Supplements that can help:
- Phosphate-binding supplements with meals, like calcium carbonate and calcium acetate, which reduce the absorption of phosphate [R]
- Niacin (vitamin B3, nicotinamide) [R, R, R, R] *niacin can decrease platelet count below normal, so it needs to be monitored
- Calcium (if you have low calcium levels from excess phosphate) [R, R]
- Bifidobacterium longum [R]
- Vitamin C [R]