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Phosphate salts

What are phosphate salts?

Phosphate sal ts is a collective term for many different combinations of the chemical phosphorus with salts and minerals. Foods that contain phosphates include dairy products, whole grains, nuts and certain meats. Phosphates found in dairy products and meat appear to be more easily absorbed by the body than phosphates found in cereal grains. Cola drinks contain a lot of phosphate - so much so that they can cause high phosphate levels in the blood.

Phosphate salts are used as medicine, among other things. Phosphate salts should not be confused with substances such as organophosphates or with tribasic sodium phosphates and tribasic potassium phosphates, which are very toxic.

Phosphate sal ts are taken orally to treat low phosphate levels in the blood, to treat high calcium levels in the blood and to prevent kidney stones. They are also used to treat osteomalacia (bone softening), which is caused by a mineral imbalance in the body. Phosphate salts are also used to improve athletic performance, as an acid blocker for gastroesophageal reflux and as a laxative to empty the bowels before operations.

In the field of dentistry, phosphate salts and calcium are applied to sensitive teeth to reduce pain.

Applied rectally, phosphate salts are used as a laxative to cleanse the bowel before operations or bowel examinations.

Doctors sometimes administer phosphate salts intravenously to treat low phosphate levels and high calcium levels in the blood and to prevent low phosphate levels in patients who are being artificially fed.

How effective are phosphate salts?

Phosphate salts are effective for treating low blood phosphate levels when administered orally or intravenously in the form of sodium and potassium phosphate.

Phosphate salts are likely to be effective for treating high levels of calcium in the blood when sodium and potassium phosphate are used.

Phosphate salts may be effective in preventing some types of kidney stones.

Phosphate salts are probably ineffective in improving aerobic performance.

There is insufficient data to assess the effectiveness of phosphate salts for sensitive teeth and heartburn, and as a laxative to cleanse the bowel before colon examinations. Further scientific research is needed in this area.

How do phosphate salts work?

Phosphates are normally absorbed through food and are important chemicals for the body. They are involved in cell structure, energy transport and storage, vitamin function and numerous other processes that are essential for health. Phosphate salts can act as a laxative by drawing more fluid into the intestines and stimulating them to move their contents faster.

Are there any safety concerns?

Phosphate salts containing sodium, potassium, aluminum or calcium appear to be safe and harmless for most people when used occasionally or for short periods of time. Daily phosphate intake should not exceed 4 grams for adults under 70 and 3 grams for the elderly.

Regular long-term use can disrupt the balance of phosphates and other chemicals in the body and should be monitored by a doctor to prevent serious side effects. Phosphate salts can irritate the digestive tract and cause stomach discomfort, diarrhea, constipation and other problems.

Phosphate salts should not be confused with substances such as organophosphates or with tribasic sodium phosphates and tribasic potassium phosphates, which are very toxic.

Precautions and warnings

Pregnancy and lactation: Phosphate salts from food sources are probably safe and harmless for pregnant and lactating women if the dosage is in the range of maximum 1250 mg phosphorus for mothers between 14 and 18 years and 700 mg for mothers over 18 years. Other amounts should only be used under medical supervision.

Children: Phosphate salts are probably safe for children when used in doses not exceeding 460 mg phosphorus in children aged 1 to 3 years, 500 mg in children aged 4 to 8 years and 1250 mg in children aged 9 to 18 years. Phosphate salts may not be safe if intake exceeds the upper tolerance threshold, which is 3 grams of phosphorus per day in children 1 to 8 years of age and 4 grams in children over 9 years of age.

Heart disease: If you suffer from heart disease, you should avoid phosphate salts that contain sodium.

Water retention (edema): You should avoid phosphate salts that contain sodium if you have cirrhosis, heart failure or other conditions that can cause edema.

High blood calcium levels: You should be careful with the use of phosphate salts if you have high blood calcium levels. Too much phosphate can lead to unwanted calcium deposits in the body.

High blood phosphate levels: People who suffer from Addison's disease, severe heart or lung disease, kidney disease, thyroid problems or liver disease are at a higher risk of developing high blood phosphate levels when using phosphate salts. If you suffer from one of these diseases, you should only use phosphate salts under medical supervision.

Kidney disease: If you suffer from kidney disease, you should only use phosphate salts under medical supervision.

Do they interact with medication?

You should be careful when combining phosphate salts with the following medications:

Bisphosphonates

Bisphosphonate medication and phosphate salts can both lower calcium levels in the body. Taking large amounts of phosphate salts in combination with these medications could lower calcium levels too much.

Are there any interactions with medicinal herbs or supplements?

Calcium, iron and magnesium

Phosphates can bind with calcium, iron and magnesium. This can reduce the body's ability to absorb phosphates, calcium, iron and magnesium. To avoid this interaction, you should take phosphate salts at least 2 hours before or after taking calcium, iron or magnesium.

Are there any interactions with food?

There are no known interactions with food.

Dosage

The following dosages have been scientifically investigated:

Oral intake:

  • To raise phosphate levels that are too low or to lower calcium levels that are too high: Physicians can measure phosphate and potassium levels in the blood and administer the exact amount of phosphate needed to correct the problem.

The following values apply for a recommended daily intake of phosphate (expressed in mg phosphorus):

  • Children from 0 to 6 months: 100 mg
  • Children from 7 to 12 months: 275 mg
  • Children between 1 and 3 years: 460 mg
  • Children between 4 and 8 years: 500 mg
  • Men and women between 9 and 18 years: 1250 mg
  • Men and women over 18 years: 700 mg

The following limits apply to the maximum tolerable amount - the maximum amount at which no undesirable side effects are to be expected - for phosphate (given in mg phosphorus):

  • Children from 1 to 8 years: 3 grams
  • Children and adults from 9 to 70 years: 4 grams
  • Adults over 70 years: 3 grams
  • Pregnant women from 14 to 50 years: 3.5 grams
  • Breastfeeding women from 14 to 50 years: 4 grams

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