Theoretically, we humans should be better adapted physiologically to the diet our ancestors were exposed to during millions of years of hominid evolution than to the diet we have been eating since the agricultural revolution a mere 10,000 years ago, and since industrialization only 200 years ago. Among the many health problems resulting from this mismatch between our genetically determined nutritional requirements and our current diet, some might be a consequence in part of the deficiency of potassium alkali salts (K-base), which are amply present in the plant foods that our ancestors ate in abundance, and the exchange of those salts for sodium chloride (NaCl), which has been incorporated copiously into the contemporary diet, which at the same time is meager in K-base-rich plant foods. Deficiency of K-base in the diet increases the net systemic acid load imposed by the diet. We know that clinically-recognized chronic metabolic acidosis has deleterious effects on the body, including growth retardation in children, decreased muscle and bone mass in adults, and kidney stone formation, and that correction of acidosis can ameliorate those conditions. Is it possible that a lifetime of eating diets that deliver evolutionarily superphysiologic loads of acid to the body contribute to the decrease in bone and muscle mass, and growth hormone secretion, which occur normally with age? That is, are contemporary humans suffering from the consequences of chronic, diet-induced low-grade systemic metabolic acidosis? Our group has shown that contemporary net acid-producing diets do indeed characteristically produce a low-grade systemic metabolic acidosis in otherwise healthy adult subjects, and that the degree of acidosis increases with age, in relation to the normally occurring age-related decline in renal functional capacity. We also found that neutralization of the diet net acid load with dietary supplements of potassium bicarbonate (KHCO3) improved calcium and phosphorus balances, reduced bone resorption rates, improved nitrogen balance, and mitigated the normally occurring age-related decline in growth hormone secretion--all without restricting dietary NaCl. Moreover, we found that co-administration of an alkalinizing salt of potassium (potassium citrate) with NaCl prevented NaCl from increasing urinary calcium excretion and bone resorption, as occurred with NaCl administration alone. Earlier studies estimated dietary acid load from the amount of animal protein in the diet, inasmuch as protein metabolism yields sulfuric acid as an end-product. In cross-cultural epidemiologic studies, Abelow found that hip fracture incidence in older women correlated with animal protein intake, and they suggested a causal relation to the acid load from protein. Those studies did not consider the effect of potential sources of base in the diet. We considered that estimating the net acid load of the diet (i. e., acid minus base) would require considering also the intake of plant foods, many of which are rich sources of K-base, or more precisely base precursors, substances like organic anions that the body metabolizes to bicarbonate. In following up the findings of Abelow et al., we found that plant food intake tended to be protective against hip fracture, and that hip fracture incidence among countries correlated inversely with the ratio of plant-to-animal food intake. These findings were confirmed in a more homogeneous population of white elderly women residents of the U.S. These findings support affirmative answers to the questions we asked above. Can we provide dietary guidelines for controlling dietary net acid loads to minimize or eliminate diet-induced and age-amplified chronic low-grade metabolic acidosis and its pathophysiological sequelae. We discuss the use of algorithms to predict the diet net acid and provide nutritionists and clinicians with relatively simple and reliable methods for determining and controlling the net acid load of the diet. A more difficult question is what level of acidosis is acceptable. We argue that any level of acidosis may be unacceptable from an evolutionarily perspective, and indeed, that a low-grade metabolic alkalosis may be the optimal acid-base state for humans.

Dietary therapies represent a potentially valuable adjunct to other epilepsy treatments, such as anticonvulsant medications, epilepsy surgery, and vagus nerve stimulation. Although the ketogenic diet (high fat, adequate protein, low carbohydrate) is the most well-established dietary therapy for epilepsy, other possible approaches include the Atkins diet (high fat, high protein, low carbohydrate), a diet enriched in polyunsaturated fatty acids, or overall restriction of calorie intake. This review discusses the current clinical status of each of these dietary approaches and suggests possible mechanisms by which they might suppress neuronal hyperexcitability and seizures.

The objective of this study was to determine whether a reduction in energy intake ameliorated the high-fat diet-enhanced spontaneous metastasis of Lewis lung carcinoma in mice. Male C57BL/6 mice were fed the AIN93G diet, a high-fat diet or a high-fat diet with a 5% restriction of the intake. Energy restriction reduced body adiposity and body weight, but maintained growth similar to mice fed the AIN93G diet. The high-fat diet significantly increased the number and size (cross-sectional area and volume) of metastases formed in lungs. Restricted feeding reduced the number of metastases by 23%, metastatic cross-sectional area by 32% and volume by 45% compared to the high-fat diet. The high-fat diet elevated plasma concentrations of proinflammatory cytokines (monocyte chemotactic protein-1, plasminogen activator inhibitor-1, leptin), angiogenic factors (vascular endothelial growth factor, tissue inhibitor of metalloproteinase-1) and insulin. Restricted feeding significantly reduced the high-fat diet-induced elevations in plasma concentrations of proinflammatory cytokines, angiogenic factors and insulin. These results demonstrated that a reduction in diet intake by 5% reduced high-fat diet-enhanced metastasis, which may be associated with the mitigation of adiposity and down-regulation of cancer-promoting proinflammatory cytokines and angiogenic factors.

Atopic eczema is the most common inflammatory skin disease of childhood in developed countries. We performed a systematic review of randomized controlled trials to assess the effects of dietary exclusions for the treatment of established atopic eczema. Nine trials (421 participants) were included, most of which were poorly reported. Six were studies of egg and milk exclusion (n = 288), one was a study of few foods (n = 85) and two were studies of an elemental diet (n = 48). There appears to be no benefit of an egg- and milk-free diet in unselected participants with atopic eczema. There is also no evidence of benefit in the use of an elemental or few-foods diet in unselected cases of atopic eczema. There may be some benefit in using an egg-free diet in infants with suspected egg allergy who have positive specific IgE to eggs - one study found 51% of the children had a significant improvement in body surface area with the exclusion diet as compared with normal diet (95% CI 1.07-2.11) and change in surface area and severity score was significantly improved in the exclusion diet as compared with the normal diet at the end of 6 weeks (MD 5.50, 95% CI 0.19-10.81) and end of treatment (MD 6.10, 95% CI 0.06-12.14). Despite their frequent use, we find little good quality evidence to support the use of exclusion diets in atopic eczema.

SCOPE:The main objectives of this study were to estimate dietary fumonisin exposure and nutrient intake in a group of patients diagnosed with celiac disease compared to non-celiac subjects.

METHODS AND RESULTS:The fumonisin level in 118 frequently consumed corn-based products was determined and dietary habits were recorded using a 7-day weighed food record. Data were then compared to those obtained for a control group. The fumonisin intake in the celiac patients was significantly higher than in controls, with mean values (± SE) of 0.395 ± 0.049 and 0.029 ± 0.006 μg/kg body weight per day, respectively. With regard to nutritional habits, celiac patients showed a preference for a high fat diet, coupled with a high intake of sweets and soft drinks and a low intake of vegetables, iron, calcium and folate.

CONCLUSION:These findings may have serious health implications for the celiac population due to the widespread occurrence of fumonisins in most of the widely consumed gluten-free products, leading to continuous exposure to this particular mycotoxin. Moreover, the recorded nutritional quality of the celiac patient's diet raises concerns regarding its long-term adequacy and its potential impact on chronic conditions such as type 2 diabetes and cardiovascular diseases.

SETTING: There is sparse epidemiologic information regarding the role of dietary factors in the development of idiopathic pulmonary fibrosis (IPF).

OBJECTIVE: To examine the relationship between specific types of fatty acids and selected foods high in fat and IPF in Japan.

DESIGN: Included were 104 cases aged>or = 40 years who had been diagnosed in the last 2 years in accordance with the most recent criteria. Controls aged>or = 40 years consisted of 56 hospitalised patients diagnosed as having acute bacterial pneumonia and four out-patients with common cold.

RESULTS: Intake of saturated fatty acids, mono-unsaturated fatty acids, n-6 polyunsaturated fatty acids and meat was independently associated with an increased risk of IPF. Specifically, the multivariate OR for comparison of the highest with the lowest quartile of intake of saturated fatty acids was 6.26 (95%CI 1.79-24.96, P for trend = 0.01) and for meat it was 7.19 (95%CI 2.15-27.07, P for trend = 0.02). Intake of cholesterol, n-3 polyunsaturated fatty acids, fish, eggs and dairy products was not related to the risk.

CONCLUSION: These findings suggest that consumption of saturated fatty acids and meat may increase the risk of IPF.

BACKGROUND:Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening.

OBJECTIVE:This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention.

DESIGN:This was a prospective study of 520 participants at high cardiovascular disease risk (mean± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire.

RESULTS:Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025).

CONCLUSIONS:This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639.

The Japanese diet is high in soy products and fish. A case-control study was conducted in Japan to investigate the relationship between dietary intake of isoflavones and fatty acids and lung function, breathlessness and chronic obstructive pulmonary disease (COPD). A total of 278 referred patients aged 50-75 years with COPD diagnosed within the past 4 years, and 340 community-based controls were assessed for respiratory symptoms and undertook spirometric measurements of lung function. A validated food frequency questionnaire was administered face-to-face to obtain information on habitual food consumption. Dietary intakes of isoflavones and fatty acids were derived from the Japanese food composition tables. The COPD patients had significantly lower habitual intakes of isoflavones (genistein and daidzein) and polyunsaturated fatty acids (PUFA; both omega-3 and omega-6) than control subjects. Lung function measures were found to be positively associated with isoflavones and PUFA intake. Substantial reductions in prevalence of COPD and breathlessness were observed for isoflavones, the respective adjusted odds ratio being 0.36 (95% confidence interval 0.19-0.68) and 0.60 (95% confidence interval 0.33-1.10) for the highest versus lowest levels of total isoflavone intake. The corresponding tests for linear trend were significant. High intakes of PUFA and omega-6 fatty acids (derived from foods excluding oils and fats as seasonings) also appeared to reduce the risks of COPD and breathlessness symptom, but no evidence of association was found for other types of fatty acids. The study provided evidence of possible protective effect of traditional Japanese diet against tobacco carcinogens.

There is evidence from a population-based study of an inverse relationship between monounsaturated fatty acids (MUFA) energy intake and age-related cognitive decline (ARCD), while high polyunsaturated fatty acids (PUFA) intake was positively associated with cognitive impairment in elderly subjects. We investigated the possible role of MUFA and PUFA on age-related cognitive changes. A population-based, prospective study was carried out on 278, 186, and 95 nondemented elderly subjects (65-84 years) evaluated for global cognitive functions (Mini-Mental State Examination, MMSE) at the first (1992-1993), second (1995-1996), and third survey (2000-2001), respectively, from the randomized cohort of Casamassima, Bari, Italy (n=704), one of the eight centers of the Italian Longitudinal Study on Aging (ILSA). MUFA and PUFA intakes were assessed at baseline with a semi-quantitative food frequency questionnaire. High MUFA and PUFA energy intakes and total energy intake were significantly associated with a better cognitive performance in a 8.5-year follow-up. In this prospective population-based study on older nondemented subjects with a typical Mediterranean diet, high MUFA and PUFA intakes appeared to be protective against ARCD.

Nutrition modification is one of the cornerstones of arterial hypertension (AH) treatment. Current American and European guidelines recommend to ingest fruits, vegetables, whole grains, and low-fat dairy products, and decrease the consumption of red meat, sugar, and trans fats. The aim of our review is to summarize the available evidence on the topic of dietary patterns associated with lower blood pressure (BP). Dietary Approach to Stop Hypertension (DASH) diet is able to lower BP equally or even more significantly than some antihypertensive drugs. The Mediterranean diet also leads to the significant reduction in BP. Vegans and vegetarians are showed to have a lower prevalence of AH than omnivores. Caloric restriction may decrease BP in normotensive, prehypertensive and hypertensive populations. BP can also be lowered by certain nutraceuticals (beetroot juice, magnesium, vitamin C, catechin-rich beverages, soy isoflavones etc). Conclusions. Diet effects on BP are mediated by the decrease of body weight, amelioration of inflammation, increase of insulin sensitivity, and antihypertensive effects of some single nutrients. Vegetarian and vegan diets have robust evidence proving their ability to reduce BP. The existence of floor effect makes these diets usable for normo- and prehypertensive people with high risk of developing AH. The dietary and nutraceutical approach to the BP lowering never has to substitute the drug treatment when the latter is needed.