The human skeletal system is a complex organ in constant equilibrium with other body parts. In addition to support and body structure, bone is the main reservoir for many minerals and essential compounds to maintain a healthy pH balance. Body damage with age makes the elderly very vulnerable to and affected by poor bone health . Diseases such as osteoporosis, characterized by weakening of bone structural matrices, increase the risk of hip fractures and other life-altering secondary symptoms. In 2010, more than 258,000 people aged 65 and older were hospitalized for hip fractures. The incidence of hip fractures is expected to increase by 12% in the United States, with 289,000 receipts projected by 2030. Another source estimates that up to 1.5 million Americans will have osteoporotic-related fractures each year. The cost to treat these people is also very large, in 1991 Medicare spent about $ 2.9 billion for care and outpatient care of hip fractures, this amount can only be expected to increase.
Video Bone health
Amino Acid Metabolism
When more sulfur-containing amino acids, methionine and cystine, are consumed than bodies that can be used for growth and repair, they are broken down to produce sulfate, or sulfuric acid among other products. Animal foods such as meat, milk, and eggs contain high protein and "animal protein intake is highly correlated with net acid excretion of the kidneys". Research that began in the early 1900s has shown a correlation between a high protein diet and increased acid excretion. One measure of the acid or base effect foods present in the body is the Renal Acid Load Potential (PRAL). Cheese with protein content of 15 g protein/100g or higher has a high PRAL value of 23.6 mEq/100 g edible portion. Meat, fish, cheese and other flour or noodles all have a PRAL of about 8.0 mEq/100 g of edible servings, where fruits and vegetables actually have a negative PRAL.
In healthy adults, bone is undergoing continuous improvement and renewal. New bone is deposited by osteoblast cells and resorbed or destroyed by osteoclast cells. This addition and bone reduction usually does not result in a net change in the overall mass of the skeleton, but the rotation process can be significantly affected by pH.
Bone Mineral Density
Bone Mineral Density (BMD) is a measure commonly used to measure bone health. Lower BMD values ​​indicate an increased risk of osteoporosis or fractures. There are various factors that affect BMD. Protein consumption has proven beneficial for bone density by providing the amino acid substrate necessary for bone matrix formation. It is also estimated that blood concentrations from bone-forming stimulants, Insulin-like Growth Factor-I (IGF-I), increase from high protein consumption and parathyroid hormone (PTH), a bone resorption stimulant, decreases. Although proteins have been shown to be beneficial for increasing bone mass, or bone mineral density, there is no significant relationship between protein intake and fracture occurrence. In other words, low BMDs can predict osteoporosis and increase the risk of fracture, but higher BMD does not mean better bone health. High BMD also correlates with other health problems. For example, higher BMD is also associated with an increased risk of breast cancer.
Acid base Homeostasis
Most metabolic processes have a specific and narrow pH range in which surgery is possible, some regulatory systems are applied to maintain homeostasis. Fluctuations away from optimum operating pH can slow or damage the reaction and may cause damage to cellular structures or proteins. To maintain body homeostasis can release excess acid or base through urine, through gas exchange in the lungs, or buffer in the blood. The blood plasma bicarbonate buffer system effectively has a stable pH and helps to withstand the extracellular pH of about 7.35. The kidneys are responsible for most acid-base settings but can excrete urine not lower than pH 5. This means that 330mL of cola cans, for example, usually range from pH 2.8-2.2, needs to be diluted. 100 fold before being excreted. Instead of producing 33L of urine from a single cola can, the body relies on a buffer to neutralize the acid. Systemic acidosis can be the result of many factors, not just diet. Anaerobic exercise, diabetes, AIDS, aging, menopause, inflammation, infection, tumors, and other injuries and fractures all contribute to acidosis. Blood has an average pH of 7.40 but interstitial fluid may vary. The skin's interstitial pH, for example, is ~ 7.1. No data available for bone.
Homocysteine ​​â € <â € <
Homocysteine, a non-protein amino acid and analogous to amino acid cystine protein, has been shown to have a negative effect on bone health. Higher concentrations of homocysteine ​​may be due to folate deficiency, vitamin B 12 B 6 . In addition, it was found that homocysteine ​​concentrations were significantly influenced by physical activity. Skeletal stimulation through physical activity promotes positive bone remodeling and lowers homocysteine ​​levels, regardless of nutritional intake. Four methods have been proposed regarding homocysteine ​​and bone interactions; increased osteoclast activity, decreased osteoblast activity, decreased bone blood flow, and direct action of homocysteine ​​on bone matrix. Homocysteine ​​inhibits lysyl oxidase responsible for post-translational collagen modification, a key component of bone structure
Osteoclast cells
Osteoclasts lie on the surface of the bone and form resorption pits by removing H to the bone surface to remove hydroxyapatite, many bone minerals, and organic components: collagen and dentin. The goal of bone resorption is to release calcium into the bloodstream for various life processes. This resorption hole is visible under an electron microscope and a typical pathway is formed from prolonged resorption. Osteoclasts have been shown to "really depend on extracellular acidification". Decrease in pH & lt; 0.1 units can cause a 100% increase in osteoclast cell activity, this effect persists with prolonged acidosis without desensitization, "strengthening the effect of simple pH differences". The osteoclasts showed little or no activity at pH 7.4 and were most active at pH 6.8 but could be further stimulated by other factors such as parathyroid hormone.
Osteoblast Cell
Osteoblasts are responsible for mineralization and construction of bone matrix. Like osteoclasts, osteoblast cell activity is directly related to the reflection of extracellular pH from osteoclast activity. At pH 7.4, where osteoclasts are inactive, osteoblasts are at peak activity. Similarly, at pH 6.9 osteoblast activity is absent. The estrogen hormone is also important for osteoblast regulation. In estrogen levels postmenopausal women decreased which had a negative effect on bone remodeling. Homocysteine ​​further exacerbates this problem by reducing estrogen receptors? transcription of mRNA. Thereby reducing the beneficial effects that estrogen plays on bone remodeling.
Maps Bone health
Bone Balance
Acidosis inhibits the mineralization of bone osteoblast matrix with a reciprocal effect on osteoclast activation. The combined response of these cells to acidosis maximizes the availability of hydroxyl ions in a solution that can be used to support protons. The use of bone to support even a small percentage of daily acid production can cause significant bone mass loss over a decade. In addition, as the body ages there is a steady decline in kidney function. Metabolic acidosis may become more severe as kidney function weakens, and the body will depend heavily on bone and blood to maintain acid-base homeostasis.
Diet
Not a single food or nutrient can provide adequate bone health by itself. Conversely, a fairly balanced diet in fruits and vegetables for vitamins, minerals, and alkalinizing substrates is considered most beneficial. High-protein diets provide large amounts of amino acids that can be degraded into acidic compounds. Protein consumption above Recommended Dietary Allowance is also known to be beneficial for calcium utilization. Overall it is understood that a high protein diet has a net benefit for bone health because changes in concentrations of IGF-I and PTH outweigh the negative effects of metabolic acid production. Sources of protein, plants or animals, no matter in terms of the acid produced from the metabolism of amino acids. Any differences in Methionine and Cysteine ​​content are not significant to affect the overall potential of renal acid (PRAL) loads from food. In addition to their acid precursor protein content, the plant also contains a large number of basic precursors. Potassium bicarbonate, the basic salt, is produced through the metabolism of other organic potassium salts: citric, malate, and gluconate, which are substantial in plants. The differences observed in PRAL are noted by differences in basic precursor content.
See also
- Copper in health
References
External links
- PRAL Calculator Calculate PRAL per meal, prescription or day total of nutritional data.
Source of the article : Wikipedia
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