Phosphorus

What is Phosphorus?

• Phosphorus is a mineral found in our bones, teeth, and DNA.   

• Phosphorus is the second most plentiful mineral found in the body [3]. 

• It also makes up our cells’ membranes and is a component of our body’s main energy source called ATP.   

• Studies show that children with ASD consume significantly less phosphorus than typically developing children.  

• The phosphorus in nuts, seeds, and beans is bound to phytate which is not as easily absorbed [3].  

• High phosphate in the body can cause calcium levels to decrease while vitamin D can cause calcium levels to increase [6].

Source: Autism Dietitian Instagram

Sources of phosphorus

• Dairy products 

  • Yogurt 

  • Milk 

  • Cheese 

• Animal protein 

  • Beef 

  • Chicken 

  • Turkey  

• Legumes* 

  • Lentils 

  • Kidney beans 

  • Peas 

• Nuts/seeds* 

  • Cashews 

  • Pumpkin seeds 

  • Sunflower seeds 

• Grains 

  • Oatmeal (see: oats) 

  • Brown Rice 

  • Whole grain bread

• Soy 

  • Tempeh 

  • Tofu

• Vegetables 

  • Potatoes 

  • Asparagus  

• Carbonated beverages  

• Many processed foods have added phosphorus 
  

• *The phosphorus in nuts, seeds, and beans is bound to phytate which is not as easily absorbed. [3]
  

Recommended Intake

These recommendations are based on the Recommended Dietary Allowance (RDA), which is the average daily level of intake sufficient to meet the nutrient recommendations of nearly all (97-98%) of healthy individuals.

Males and Females

• o-6 months: 100 mg/day

• 7-12 months:275 mg/day 

• 1-3 years: 460 mg/day 

• 4-8 years: 500 mg/day 

• 9-13 years: 1,250 mg/day 

• 14-18 years:1,250 mg/day 

• 19-50 years: 700 mg/day 

• 51+ years: 700 mg/day

Deficiency

Phosphorus deficiency is rare because it is naturally present in many foods along with the addition of phosphorus in many processed foods. Some people may have more trouble obtaining phosphorus in their diet. 

• Some Individuals at Risk for Phosphorus Deficiency Include:  

  • Premature infants 

  • Severely malnourished individuals 

  • Those with certain genetic disorders  

  • Individuals with diabetes 

  • Children with restrictive diets

  • Individuals with excessive calcium intake

• Some Symptoms of Phosphorus Deficiency Include: 

  • Anemia 

  • Loss of appetite 

  • Muscle weakness 

  • Coordination problems 

  • Bone pain 

  • Soft and deformed bones 

  • Confusion  

Toxicity

Phosphorus toxicity can be caused by consuming foods grown in areas with excess phosphorus in the soil, by over-supplementation of phosphorus, and kidney disease. 

Some symptoms of phosphorus toxicity include:  

• Diarrhea 

• Joint pain 

• Muscle pain 

• Nausea/vomiting

• Diarrhea 

• Red itchy eyes 
  
  The Tolerable Upper Intake Level (UL): Maximum daily intake unlikely to cause adverse health effects.

Males and Females

• 1-3 years: 3,000 mg/day 

• 4-8 years: 3,000 mg/day 

• 9-13 years: 4,000 mg/day 

• 14-18 years: 4,000 mg/day 

• 19-50 years: 4,000 mg/day 

• 51-69 years: 4,000 mg/day 

• 70+ years: 3,000 mg/day

Supplements

Phosphorus supplements are available featuring only phosphate, but it is more commonly found in combination with other ingredients. Some forms of phosphate include: dipotassium phosphate, disodium phosphate, phosphatidylcholine, phosphatidylserine, and in the form of a multivitamin [1].  

DISCLAIMER: Before starting any supplement or medication, always consult with your healthcare provider to ensure it is a good fit for your child. Dosage can vary based on age, weight, gender, and current diet.

Phosphorus & Autism in the Research

• Children with autism were seen to consume significantly less phosphorus than their typically developing peers [2][5].  

• In one study, adolescent boys with ASD were found to consume less phosphorus and have lower bone mineral density [4].  

• Another study showed that children with ASD had significantly lower phosphorus levels and calcium levels when compared to children without ASD diagnosis [7].

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• References

  [1] Phosphorus Fact Sheet for Consumers. Nih.gov. Accessed February 25, 2021.  https://ods.od.nih.gov/factsheets/Phosphorus-Consumer/ 

  [2] Esteban-Figuerola P, Canals J, Fernández-Cao JC, Arija Val V. Differences in food consumption and nutritional intake between children with autism spectrum disorders and typically developing children: A meta-analysis [published correction appears in Autism. 2020 Feb;24(2):531-536]. Autism. 2019;23(5):1079-1095. doi:10.1177/1362361318794179 

  [3] National Research Council (US) Committee on Diet and Health. Diet and Health: Implications for Reducing Chronic Disease Risk. Washington (DC): National Academies Press (US); 1989. 13, Minerals. Available from: https://www.ncbi.nlm.nih.gov/books/NBK218735/

  [4] Neumeyer AM, Cano Sokoloff N, McDonnell EI, et al. Nutrition and Bone Density in Boys with Autism Spectrum Disorder. J Acad Nutr Diet. 2018;118(5):865-877. doi:10.1016/j.jand.2017.11.006 

  [5] Tsujiguchi H, Miyagi S, Nguyen TTT, et al. Relationship between Autistic Traits and Nutrient Intake among Japanese Children and Adolescents. Nutrients. 2020;12(8):2258. Published 2020 Jul 28. doi:10.3390/nu12082258 

  [6] Shaker JL, Deftos L.  Calcium and phosphate homeostasis. In:  LJ Groot,  G Chrousos,  K Dungan, et al. eds.  Endotext.  South Dartmouth, MA:  MDText.com, Inc.; 2000. 

  [7] Afroz, S., Siddiqi, U., Mahruba, N., Shahjadi, S., & Begum, S. (2020). Serum Calcium and Phosphate in Children with Autism Spectrum Disorder. Journal of Bangladesh Society of Physiologist, 15(2), 72-77. https://doi.org/10.3329/jbsp.v15i2.50921

Authors

Suzy Morris, Dietetic Intern

Contributed by Brittyn Coleman, MS, RDN/LD, CLT