Sodium intake

Sodium Intake. Where salt is readily available, most of the world s population chooses to consume about 6,000—11,000 mg of salt or sodium chloride a day so that average daily sodium intake from all sources is 3,450 mg (8,770 mg NaCl) (13). The U.S. EDA s GRAS review puts the amount of naturally occurring sodium in the American diet at 1000—1500 mg/d, equivalent to the amount of sodium in approximately 2500—3800 mg NaCl. Thus the average daily intake of NaCl from food-grade salt used in food processing (qv) and from salt added in cooking or at the table is from 4960—6230 mg NaCl. The requirement for salt in the diet has not been precisely estabUshed, but the safe and adequate intake for adults is reported as 1875—5625 mg (14). The National Academy of Sciences recommends that Americans consume a minimum of 500 mg/d of sodium (1250 mg/d salt) (6,15). 

The use of the potassium salt of benzoic acid is relatively new. Concerns regarding sodium intake and its possible relationship to high blood pressure have caused some soft drink manufacturers to switch to potassium benzoate. 

This type of water softener shouldn t be used if you re trying to reduce sodium intake. 

High levels of sodium in the diet are linked to high blood pressure. Doctors often recommend that individuals who need to lower their blood pressure limit their sodium intake, but the sodium in table salt is a big part of most people s diets. They can turn to salt substitutes instead. 

In addition to excess sodium intake, abnormal renal sodium retention may be the primary event in the development of hypertension, and it includes abnormalities in the pressure-natriuresis mechanism. In hypertensive individuals, this theory proposes a shift in the control mechanism preventing the normalization of blood pressure. The mechanisms behind the resetting of the pressure-natriuresis curve may include afferent arteriolar vasoconstriction, decreased glomerular ultrafiltration, or an increase in tubular sodium reabsorption.4 Other theories supporting abnormal renal sodium retention suggest a congenital reduction in the number of nephrons, enhanced renin secretion from nephrons that are ischemic, or an acquired compensatory mechanism for renal sodium retention.9... 

Dietary sodium restriction Reduce dietary sodium intake to no more than 100 mmol per day (2.4 g sodium or 6 g sodium chloride) 2-8 mm Hg... 

Limit daily sodium intake to 2.4 grams (6 grams of salt) for blood pressure control. 

Assess dietary sodium intake by patient food recall or by spot urine sodium/potassium ratio for appropriate sodium excretion. 

The kidney is unable to adjust to abrupt changes in sodium intake in patients with severe CKD. Therefore, patients should be advised to refrain from adding salt to their diet, but should not restrict sodium intake. Changes in sodium intake should occur slowly over a period of several days to allow adequate time for the kidney to adjust urinary sodium content. Sodium restriction produces a negative sodium balance, which causes fluid excretion to restore sodium balance. The resulting volume contraction can decrease perfusion of the kidney and hasten the decline in GFR. Saline-containing intravenous (IV) solutions should be used cautiously in patients with CKD because the salt load may precipitate volume overload. 

Fluid restriction is generally unnecessary as long as sodium intake is controlled. The thirst mechanism remains intact in CKD to maintain total body water and plasma osmolality near normal levels. Fluid intake should be maintained at the rate of urine output to replace urine losses, usually fixed at approximately 2 L/day as urine concentrating ability is lost. Significant increases in free water intake orally or intravenously can precipitate volume overload and hyponatremia. Patients with stage 5 CKD require renal replacement therapy to maintain normal volume status. Fluid intake is often limited in patients receiving hemodialysis to prevent fluid overload between dialysis sessions. 

Angiotensin I Salt intake and ACE Variation in the efficacy of reduced sodium intake (90) Susceptibility to essential hyperten-... 

A high sodium intake and increased circulating natriuretic hormone inhibition of intracellular sodium transport, resulting in increased vascular reactivity and a rise in BP and / Increased intracellular concentration of calcium, leading to altered vascular smooth muscle function and increased peripheral vascular resistance. 

Excessive sodium intake (sources may be dietary, IV fluids, and drugs)... 

Hypernatremia and fluid retention commonly occur, necessitating restricting daily sodium intake to no more than 3 g. All sources of sodium, including antibiotics, need to be considered when calculating daily sodium intake. 

The kidney s ability to adjust to abrupt changes in sodium intake is diminished in patients with ESRD. Sodium restriction beyond a no-added-salt diet is not recommended unless hypertension or edema is present. A negative sodium balance can decrease renal perfusion and cause a further decline in GFR. 

Reassessment of current pharmacotherapy Salt, sodium intake... 

It is extremely important to select the correct type of nutrition when feeding severely malnourished individuals or patients. The provision of food can be dangerous unless carefully controlled as it can lead to what is known as the refeeding syndrome . This is characterised by a rapid increase in extracellular volume, due to increased sodium intake, and decreased blood levels of phosphate and potassium due to increased levels of insulin which stimulate the entry of these into muscle. (The latter changes are also seen when type 1 diabetic patients in a severe hyper-glycaemic state are treated with insulin.) A recommended refeeding schedule is as follows ... 

Regular exercise helps in lowering blood pressure especially in obese patients. A sedentary lifestyle is often implicated in cardiovascular disease, such as hypertension. Other non-pharmacological methods that help reduce blood pressure include decrease in sodium intake, moderation of alcohol consumption, avoiding stress and stopping smoking for smokers. Healthy food... 

Lithium has been used clinically for many years in the treatment of mania (Dl, S27), and latterly as a prophylactic in recurrent depression (Bl, B2, CIO, H16). For a short while, about 1948, lithium salts were sold as a common salt substitute for patients on low sodium intake diets, but its high toxicity, culminating in a number of deaths, led to its discontinuance for this purpose. 

Life-style modifications Weight reduction Moderation of alcohol intake Regular physical activity Reduction of sodium intake Smoking cessation... 

Appel LJ, Espeland MA, Easter L, Wilson AC, Eohnar S, Lacy CR. Effects of reduced sodium intake on hypertension control in older individuals results from the Trial of Nonpharmacologic Interventions in the Elderly (TONE). Arch Intern Med 2001 161(5) 685-93. 

Most patients should eat a diet with no added salt because of associated hypertension or edema. In dialysis patients, sodium intake should be reduced in patients who gain excessive weight between dialysis. Potassium restriction is not usually necessary until oliguria supervenes. Dialysis patients, however, should be educated to what foods are high in potassium, such as citrus foods, nuts, bananas, in order to avoid very high serum levels of potassium before each dialysis. Water restriction may be necessary if predialysis hyponatremia becomes prominent. 

Three generally accepted mechanisms are involved in the regulation of renin secretion (Fig. 18.2). The first depends on renal afferent arterioles that act as stretch receptors or baroreceptors. Increased intravascular pressure and increased volume in the afferent arteriole inhibits the release of renin. The second mechanism is the result of changes in the amount of filtered sodium that reaches the macula densa of the distal tubule. Plasma renin activity correlates inversely with dietary sodium intake. The third renin secretory control mechanism is neurogenic and involves the dense sympathetic... 

Larsson, S. C., Virtanen, M. J., Mars, M., Mannisto, S., Pietinen, R, Albanes, D., Virtamo, J. (2008). Magnesium, calcium, potassium, and sodium intakes and risk of stroke in male smokers. Arch. Intern. Med., 168,459 65. 

In addition to noncompliance with medication, causes of failure to respond to drug therapy include excessive sodium intake and inadequate diuretic therapy with excessive blood volume, and drugs such as tricyclic antidepressants, nonsteroidal anti-inflammatory... 

Vollmer WM et al Effects of diet and sodium intake on blood pressure Subgroup analysis of the DASH-Sodium trial. Ann Intern Med 2001 135 1019. [PMID 11747380]... 

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