Observational studies suggest that people who eat more phosphorus gain less weight.
However, the effects of phosphorus supplementation on weight loss have never been studied in humans.
For this reason, a team of scientists recently conducted a study. Below is a detailed summary of their results, published in Nutrition & Diabetes.
Phosphorus is a dietary mineral that is essential for every cell in the body.
Most of it is found in your bones and teeth. In plants and animals, phosphorus is bound to oxygen, forming phosphate.
Phosphate is found in most food in varying amounts, but the best dietary sources are dairy products, meat and fish (1).
Interestingly, scientists have speculated that poor phosphorus status may increase the risk of weight gain and obesity.
However, human trials are needed to confirm these findings.
A group of researchers from Beirut, Lebanon, conducted a study examining the effects of phosphorus supplementation on body weight.
This was a double-blind, randomized controlled trial in overweight, but otherwise healthy, adults aged 18–45 years.
The participants were randomly assigned to one of two groups:
- Phosphorus group: Participants took phosphorus supplements with a meal 3 times a day for 12 weeks, amounting to 1,125 mg per day.
- Placebo group: Participants took the same amount of a placebo.
At the beginning, middle and end of the study, the researchers measured body weight, waist circumference, subjective appetite scores, and fasting levels of phosphorus, creatinine, C-reactive protein, blood lipids, blood sugar and insulin.
A total of 47 participants completed the study, or 75% of those who were recruited.
Bottom Line: This was a 12-week, randomized controlled trial examining the effects of a phosphorus supplement on body weight and appetite.
Finding 1: Phosphorus Caused Weight Loss and a Reduction in Waist Circumference
At the end of the study, those in the phosphorus group had lower body weight, body mass index and waist circumference, compared to the placebo group, as shown in the chart below.
In the phosphorus group, body weight decreased by 0.65 kg (1.4 lbs), whereas body weight increased by 1.13 kg (2.5 lbs) in the placebo group.
However, note that the present study is the first human trial to examine the effects of phosphorus on body weight. Further studies are needed to confirm its results.
Bottom Line: Supplementing with phosphorus caused weight loss and a reduction in waist circumference. These results need to be confirmed by further studies.
Finding 2: Phosphorus Reduced Appetite
In the phosphorus group, subjective ratings of appetite decreased.
These included appetite, the amount of food needed to reach fullness and the number of snacks eaten.
The findings are supported by one study in which phosphorus intake reduced food intake at a subsequent meal (9).
Bottom Line: Supplementing with phosphorus reduced subjective ratings of appetite.
Finding 3: Blood Levels of Phosphorus Did Not Increase
Levels of phosphorus in blood plasma did not increase among those participants who got phosphorus supplements.
Bottom Line: The study suggests that phosphorus intake is not reflected in increased fasting levels of phosphorus in blood, supporting earlier findings.
The study had no obvious major limitations.
However, the methods section of the article lacks information. For example, there is no information on the type of phosphorus/phosphate supplement used.
Additionally, phosphorus levels in blood plasma did not increase in people who got phosphorus supplements.
While this is supported by previous studies suggesting phosphorus levels in blood do not reflect intake, it also means the researchers were unable to test compliance.
Bottom Line: This study had no apparent limitations, but the paper is lacking information on the supplement that was used.
Summary and Real-Life Application
In short, this study showed that phosphorus supplements may promote weight loss.
They do this, most likely, by suppressing appetite and calorie intake.
Since this is the first study to show that phosphorus reduces body weight, further studies are needed to confirm its findings.