- W. Altorf-van der Kuil (1)
- M.F. Engberink (1)
- J.M. Geleijnse (2)
- Lieke Gijsbers (1)
- D.E. Grobbee (1)
Vascular effects of sodium and potassium intake
Gijsbers, Lieke - \ 2017
Wageningen University. Promotor(en): Marianne Geleijnse; Pieter van 't Veer. - Wageningen : Wageningen University - ISBN 9789463436267 - 161
sodium - potassium - vascular system - hypertension - blood pressure - mineral supplements - endothelium - blood vessels - heart rate - osmoregulation - human nutrition research - randomized controlled trials - cardiovascular diseases - natrium - kalium - vaatsysteem - hypertensie - bloeddruk - minerale supplementen - endotheel - bloedvaten - hartfrequentie - osmoregulatie - voedingsonderzoek bij de mens - gestuurd experiment met verloting - hart- en vaatziekten
Cardiovascular diseases (CVD) are the main cause of death worldwide. Annually, about 17.5 million people die from CVD, accounting for ~30% of deaths worldwide. Elevated blood pressure (BP) is a major risk factor for CVD and the largest single contributor to global mortality. BP is a modifiable risk factor that is largely determined by lifestyle factors, including diet. Dietary minerals, in particular sodium and potassium, play an important role in BP regulation. While adverse effects of sodium and beneficial effects of potassium on BP have repeatedly been shown in human intervention studies, evidence on other vascular effects of these dietary minerals is still scarce. Therefore, we investigated the BP effects of sodium and potassium intake in healthy humans in a broader (patho)physiological context, focusing also on endothelial function, arterial stiffness, fluid regulation and heart rate.
In Chapter 2, the effects of sodium and potassium supplementation on BP and arterial stiffness were examined by means of a randomized placebo-controlled crossover trial. Thirty-six untreated Dutch individuals with mildly elevated BP on a fully controlled diet that was relatively low in sodium (2-3 g/d) and potassium (2-3 g/d) received capsules with sodium (3 g/d), potassium (3 g/d) or placebo, for 4 weeks each, in random order. After each intervention, fasting office BP, 24-h ambulatory BP and measures of arterial stiffness were assessed. The results of this study showed that increased sodium intake strongly raised office and ambulatory systolic BP (7-8 mmHg) whereas increased potassium intake lowered systolic BP (3-4 mmHg). Potassium supplementation increased ambulatory HR, but office HR was not affected. Measures of arterial stiffness were not materially affected by increased sodium or potassium intake, possibly due to the relatively short intervention period.
In the same study we investigated the effects of increased sodium and potassium intake on the functional measure of endothelial function (flow-mediated dilation), and on a comprehensive set of biomarkers of endothelial dysfunction and low-grade inflammation (Chapter 3). Four weeks of supplemental sodium had no effect on brachial flow-mediated dilation, or on the blood biomarkers of endothelial dysfunction and low-grade inflammation, except for an increase in serum endothelin-1 (a biomarker of endothelial dysfunction). Potassium supplementation improved flow-mediated dilation by 1.2% and tended to lower the low-grade inflammation marker interleukin-8. This suggests that potassium may beneficially influence vascular health by improving endothelial function.
In a post-hoc analysis of the same study in 35 untreated individuals, the humoral effects of supplemental sodium and potassium were assessed using a panel of markers that are involved in osmoregulation and volume regulation (Chapter 4). Results showed that supplemental sodium increased plasma natriuretic peptides and plasma copeptin, and suppressed the renin-angiotensin system. Supplemental potassium decreased plasma MR-pro-ANP, increased plasma copeptin, and stimulated the renin-angiotensin system. These findings suggest that the mineral-induced changes in BP elicit several counter regulatory mechanisms to maintain volume homeostasis.
In Chapter 5, the effect of potassium supplementation on heart rate was assessed in a meta-analysis of 22 randomized, placebo-controlled trials in healthy adults. Overall, increasing potassium intake by 2-3 g/d for at least two weeks did not affect resting heart rate. 24-h Ambulatory heart rate was not significantly affected in subgroup analysis of 4 RCTs, including ours. Other subgroup analyses for characteristics of the study and study population also showed no significant effects, and there was no evidence for a dose-response relationship. These results suggest that increasing potassium intake is not expected to adversely affect heart rate in apparently healthy adults.
In Chapter 6, BP associations for sodium and potassium intake using different dietary assessment methods were examined. Data of 993 healthy Dutch adults not on antihypertensive medication were analyzed using a cross-sectional approach. Sodium and potassium intake were estimated from two non-consecutive 24-h urinary samples (considered as the gold standard), two non-consecutive web-based 24-h recalls, and a validated 180-item food frequency questionnaire (FFQ). This study showed no significant associations of sodium intake with BP, regardless of the dietary assessment method used. Potassium intake estimated from 24-h urine and FFQ was inversely associated with BP (~1.5 mmHg reduction per 1 g/d increment). This suggests that dietary assessment methods in cross-sectional studies may be inadequate for estimating the association of sodium intake with BP, but may yield reliable results for potassium intake.
As discussed in Chapter 7, the studies presented in this thesis indicate that increasing sodium intake from a recommended level to a level that is common in Western societies for four weeks strongly raises BP in individuals with an untreated mildly elevated BP. The results for endothelial function and arterial stiffness are inconclusive, and hence more (longer-term) studies are warranted. Increasing the intake of potassium lowers BP and improves endothelial function, even in individuals on a relatively low-sodium diet. Both sodium and potassium intake affected fluid parameters, likely indicating that compensatory responses are stimulated to maintain body fluid balance. Although in our RCT ambulatory heart rate was increased after supplemental potassium, the meta-analysis showed that increasing potassium intake is unlikely to affect heart rate in apparently healthy adults. When evaluating the effectiveness of sodium and potassium intake on cardiovascular health, results obtained from observational studies should be interpreted with caution, particularly for sodium intake.
Around the world people consume on average 9-12 g of salt and 2-4 g of potassium on a daily basis. A more optimal intake of sodium and potassium can be achieved through adherence to dietary guidelines and product reformulation by food industry. This could reduce BP by more than 10 mmHg and lower the number of cardiovascular deaths by at least one-quarter in Western populations.
Dietary protein, blood pressure and mortality : the value of repeated measurements
Tielemans, S.M.A.J. - \ 2016
Wageningen University. Promotor(en): Marianne Geleijnse; Daan Kromhout, co-promotor(en): Hendriek Boshuizen. - Wageningen : Wageningen University - ISBN 9789462577916 - 169 p.
cardiovascular diseases - blood pressure - dietary protein - mortality - cardiovascular disorders - hypertension - urea - meta-analysis - antihypertensive agents - plant protein - animal protein - hart- en vaatziekten - bloeddruk - voedingseiwit - mortaliteit - hart- en vaatstoornissen - hypertensie - ureum - meta-analyse - antihypertensiva - plantaardig eiwit - dierlijk eiwit
Cardiovascular diseases (CVD) are the main cause of death worldwide. In 2012, about 17.5 million people died from CVD, accounting for 30% of all deaths. High blood pressure (BP) is a major cardiovascular risk factor, which was responsible for 10.4 million deaths in 2013. Diet and lifestyle play an important role in the etiology of hypertension. Maintenance of a desirable body weight, physical activity, and low intake of alcohol and salt are well-known measures to avoid high BP. Whether dietary protein, or more specifically plant and animal protein, could contribute to maintaining a healthy BP is less clear. The association between BP and CVD mortality has been extensively investigated. BP in prospective studies can be analyzed using different approaches, such as single BP (measured at one moment in time), single BP adjusted for regression dilution, average BP, and trajectories of BP. It is not yet clear which of these approaches is to be preferred for CVD risk prediction.
This thesis is centered on BP as a major cardiovascular risk factor. In the first part (Chapter 2, 3 and 4), the relation of dietary protein intake with BP level and change was examined. In the second part (Chapter 5 and 6), various approaches for analyzing repeated BP measurements were compared in relation to CVD and all‑cause mortality risk. The final chapter discusses the main findings and their implications.
Chapter 2 describes the association of 24-h urinary urea excretion, as a biomarker of total protein intake, with 9-year incidence of hypertension. We analyzed data of ~4000 men and women aged 28–75 years, who participated in the Prevention of Renal and Vascular Endstage Disease (PREVEND) study, a prospective cohort study. BP was measured four times during 1997–2009 and participants were followed for hypertension incidence, defined as BP ≥140/90mmHg or use of antihypertensive medication. Urea excretion was assessed in two consecutive 24-h urine collections at baseline and approximately 4 years later, from which total protein intake was estimated. Protein intake based on 24-h urinary urea excretion was not associated with incident hypertension.
Chapter 3 presents findings for long-term total, animal and plant protein intake in relation to 5‑year BP change. Analyses were based on 702 observations of 272 men who participated in the Zutphen Elderly Study. Participants did not use antihypertensive medication and were initially free of CVD. Physical and dietary examinations were performed in 1985, 1990, 1995, and 2000. BP was measured twice at each examination and protein intake was assessed using the cross-check dietary history method. The upper tertiles of plant protein intake were associated with a mean 5‑year change in systolic BP of ‑2.9 mmHg (95% CI: ‑5.6, ‑0.2), compared with the bottom tertile. Total and animal protein intake was not associated with BP.
Chapter 4 describes a meta‑analysis of 12 observational studies and 17 randomized controlled trials (RCTs) of dietary protein, including animal and plant protein, in relation to BP. Protein intake in prospective cohort studies was not associated with incident hypertension. For RCTs that used carbohydrate as a control treatment, the pooled BP effect was ‑2.1 mmHg systolic (95% CI: ‑2.9, ‑1.4) for a weighted mean contrast in protein intake of 41 grams per day. There was no differential effect of animal and plant protein on BP.
Chapter 5 describes repeated BP measures and their association with CVD and all‑cause mortality and life years lost in two prospective and nearly extinct cohorts of middle-aged men, the Minnesota Business and Professional Men Study (n=261) and the Zutphen Study (n=632). BP was measured annually during 1947–1957 in Minnesota and 1960–1970 in Zutphen. After 10 years of BP measurements, men were followed until death on average 20 years later. Each 25-mmHg increase in average SBP was associated with a 49% to 72% greater CVD mortality risk, 34% to 46% greater all-cause mortality risk and 3 to 4 life years lost. Four systolic BP trajectories were identified, in which mean systolic BP increased by 5 to 49 mmHg in Minnesota and 5 to 20 mmHg in Zutphen between age 50 and 60. In Zutphen, a 2-times greater CVD and all-cause mortality risk and 4 life years lost were observed when comparing trajectories. In Minnesota, associations were twice as strong. BP trajectories were the strongest predictors of CVD mortality and life years lost in Minnesota men, whereas in Zutphen men, the average BP was superior to other measures.
Chapter 6 presents findings for average BP and BP trajectories in relation to CVD and all-cause mortality, taking into account antihypertensive medication. A total of 762 participants aged ≥50 years of the Rancho Bernardo Study were examined five times from 1984 to 2002 and monitored for cause‑specific mortality from 2002 to 2013. Each 20‑mmHg increment in average systolic BP was associated with 35% greater CVD mortality and 25% greater all-cause mortality risk. We identified four trajectories for systolic BP for which BP increases ranged from 5 to 12 mmHg between age 60 and 70. In individuals who belonged to the higher trajectories, 2‑3 times greater CVD mortality and 1.5-times greater all-cause mortality risks were observed, compared to those who belonged to the lowest trajectory. Long-term systolic BP trajectories and average systolic BP were both significant predictors of CVD and all-cause mortality. The associations were not modified by antihypertensive medication.
As described in Chapter 7, various approaches were used to study the relation between protein intake and BP. Findings from individual studies and a meta-analysis suggest that dietary protein per se does not affect BP within the range of intake generally consumed in the Netherlands. Replacing carbohydrates by protein, however, has a beneficial effect on BP.
Moreover, this thesis showed that BP trajectories are not superior to average BP in predicting CVD and all-cause mortality. A few repeated BP measurements, e.g. three or four, are likely to be sufficient for obtaining a reliable average BP and had a similar predictive value for mortality compared to BP trajectories. Therefore, average BP can be considered the most practical tool for estimating mortality risk.
Dietary protein and blood pressure : epidemiological studies
Altorf-van der Kuil, W. - \ 2012
Wageningen University. Promotor(en): Pieter van 't Veer, co-promotor(en): Marianne Geleijnse; Marielle Engberink. - S.l. : s.n. - ISBN 9789461733078 - 203
voedingseiwit - bloeddruk - epidemiologische onderzoeken - eiwitinname - dieet - dietary protein - blood pressure - epidemiological surveys - protein intake - diet
Zout, bloeddruk en hart- en vaatziekten
Geleijnse, J.M. - \ 2011
In: Hart- en vaatziekten in Nederland 2011 / Vaartjes, I., van Dis, I., Visseren, F.L.J., Bots, M.L., Den Haag : Hartstichting - ISBN 9789075131703 - p. 73 - 90.
zout - reductie - hart- en vaatziekten - bloeddruk - hypertensie - natriumchloride - zoutgehalte - ziektepreventie - gezondheidsbevordering - salt - reduction - cardiovascular diseases - blood pressure - hypertension - sodium chloride - salinity - disease prevention - health promotion
Dit hoofdstuk richt zich op het belang van zoutreductie in de Nederlandse bevolking, waarbij achtereenvolgens het verband met bloeddruk en hart- en vaatziekten, de dagelijkse zoutinname en bronnen van zout, de potentiële gezondheidswinst door zoutreductie en lopende initiatieven op het gebied van zoutreductie in de bevolking besproken worden.
Nutritional interventions and blood pressure : role of specific micronutrients and other food components
Mierlo, L.A.J. van - \ 2010
Wageningen University. Promotor(en): Frans Kok, co-promotor(en): Marianne Geleijnse; P.L. Zock. - [S.l.] : S.n. - ISBN 9789085856900 - 187
bloeddruk - dieet - ziektepreventie - maatregel op voedingsgebied - sporenelementen - hypertensie - mineralen - blood pressure - diet - disease prevention - nutritional intervention - trace elements - hypertension - minerals
Elevated blood pressure is an important risk factor for cardiovascular diseases (CVD). Modest reductions in blood pressure at the population level, as can be achieved by dietary and lifestyle changes, have a large impact on the burden of CVD. Blood pressure is regulated by several physiological mechanisms, including vascular endothelial function.
The studies described in this thesis examined the potential effects of various micronutrients and other food components on blood pressure and endothelial function. The first aim was to assess the importance of selected minerals on population blood pressure levels and the second was to investigate the vascular effects of food components other than minerals that have recently attracted attention in the field of nutrition and blood pressure.
A review of 21 national surveys showed that current dietary potassium intakes are suboptimal (1.7-3.7 gram per day). We estimated that increasing intakes to the recommended level of 4.7 gram per day can reduce population systolic blood pressure by 2-3 mmHg in Western countries, this effect being similar to that which can be achieved by reducing current sodium intakes to recommended levels. Our meta-analysis of 40 randomized controlled intervention studies showed that increasing calcium intake by ~1200 mg per day significantly lowers systolic blood pressure by 2 mmHg and diastolic blood pressure by 1 mmHg. This effect tended to be stronger in populations with lower intakes (<800 mg per day). In an 8-week placebo controlled parallel study in 124 subjects with elevated blood pressure, we found no significant blood pressure lowering effects of skimmed milk enriched in potassium (1500 or 750 mg per daily serving) combined with calcium, magnesium, selenium, vitamin C and vitamin E. However, this study was not designed to detect reductions in systolic blood pressure of 2-3 mmHg, which are still relevant at the population level.
In two 4-week placebo controlled cross-over studies, in 162 subjects with untreated elevated blood pressure, we could not demonstrate an antihypertensive effect of a yogurt drink with lactotripeptides obtained by enzymatic hydrolysis (study 1: 10.2 mg per day; study 2: 4.6 mg per day plus 350 mg added potassium). In another 2-week placebo controlled cross-over study in 35 healthy males we found no consistent effect on endothelial function and blood pressure of ~800 mg polyphenols per day from either a wine-grape mix or grape seeds. Finally, a meta-analysis of 14 randomized controlled intervention studies showed that folic acid at a high dose (≥5000 g per day), which can not be attained with a regular diet, significantly improved flow-mediated dilation by 8%.
Adequate potassium and calcium intakes can play an important role in the prevention of hypertension at the population level. Lactotripeptides have no relevant effect on blood pressure in Caucasian populations. The potential of grape polyphenols and folic acid to improve endothelial function is limited.
Multiple actions are needed to lower blood pressure at the population level and reduce the burden of CVD. To improve intakes of potassium and calcium, public health measures should re-emphasize the intake of fruits, vegetables, and low-fat dairy products. Further optimization of mineral intakes, in particular reduction of sodium intake, requires collaborative actions of government and food industry.
Zuivelconsumptie, bloeddruk en hypertensie : observationele studies en interventieonderzoek
Engberink, M.F. - \ 2009
Wageningen University. Promotor(en): Evert Schouten; Frans Kok, co-promotor(en): Marianne Geleijnse. - [S.l. : S.n. - ISBN 9789085853619 - 143
melkproducten - bloeddruk - hypertensie - gestuurd experiment met verloting - epidemiologische onderzoeken - maatregel op voedingsgebied - voedselopname - dieetrichtlijnen - nederland - milk products - blood pressure - hypertension - randomized controlled trials - epidemiological surveys - nutritional intervention - food intake - dietary guidelines - netherlands
Diet and lifestyle play an important role in maintaining a healthy blood pressure. Whether intake of dairy products could reduce population blood pressure remains to be established. We examined the association of (specific types of) dairy food intake with blood pressure and risk of hypertension using data from two Dutch population-based cohort studies; i.e. the MORGEN study and the Rotterdam study. Blood pressure level was not consistently associated with overall dairy intake or intake of specific dairy foods in 21,553 Dutch adults from the MORGEN study. However, both in the MORGEN study and in the Rotterdam study, the risk of hypertension was reduced by ~20% in subjects who consumed more than 150 mL of low-fat dairy per day. Other dairy foods, i.e. fermented dairy, high-fat dairy, milk and milk products, and cheese, were not consistently associated with risk of hypertension. In addition, we assessed the effect of two dairy components on human blood pressure, i.e. lactotripeptides and cis-9, trans-11 conjugated linoleic acid, in controlled intervention studies. These dairy components did not affect blood pressure.
Voeding en gezondheid - hypertensie
Geleijnse, J.M. ; Grobbee, D.E. - \ 2003
Nederlands Tijdschrift voor Geneeskunde 147 (2003)21. - ISSN 0028-2162 - p. 996 - 1000.
voeding - gezondheid - hypertensie - dieetadvisering - zout - ziektepreventie - kalium - magnesium - bloeddruk - nutrition - health - hypertension - diet counseling - salt - disease prevention - potassium - blood pressure
A healthy diet plays an important role in both the prevention and treatment of hypertension. Very good results have been obtained with the "Dietary approaches to stop hypertension (Dash)" combination diet. Salt reduction has a favourable effect; simultaneous increases in potassium and magnesium intake could have an additional beneficial effect. The use of low-sodium high-potassium mineral salt could make a useful contribution to prevention and treatment. These dietary measures, combined with weight loss and physical exercise, may prevent drug treatment
Blood pressure : trends, determinants and consequences
Leer, E.M. van - \ 1995
Agricultural University. Promotor(en): Daan Kromhout; J.C. Seidell. - S.l. : Van Leer - ISBN 9789054853633 - 131
bloeddruk - nederland - blood pressure - netherlands
<p>Trends in blood pressure, prevalence and treatment of hypertension were studied in 30,000 men and women aged 37-43 years during the period 1974-1980, in 80,000 men aged 33-37 years during the period 1981-1986 and 36,000 in men and women aged 20-59 years during the period 1987-1991. Between 1974 and 1991 changes in systolic and diastolic blood pressure were minor with the exception of an increase in the prevalence of hypertension in men between 1974-1980. Between 1981 and 1991 the prevalence of hypertension remained stable in men and in women between 1987 and 1991. More women than men were treated for hypertension; this did not change between 1974 and 1991. An increase in the percentage of treated hypertensive men between 1974 and 1986 was followed by a decrease in the period between 1987 and 1991 when a decrease in the treatment of hypertension in women was also seen.<p>In a cross-sectional analysis in about 30,000 men and women aged 20-59 years a linear relation between alcohol consumption and blood pressure was observed in men. The results in women suggest a threshold of two glasses per day. In this study it was observed that gender, age and smoking were important effect modifiers of the alcohol-blood pressure association. An inverse association was observed between blood pressure and the intake of potassium and magnesium in both men and women. Dietary calcium was inversely related to systolic blood pressure in women and to systolic and diastolic blood pressure in both men and women. Men and women consuming a diet high in potassium, magnesium and calcium had about 2 mmHg lower blood pressure than their counterparts consuming a diet low in these minerals.<p>In a 12-year follow-up study in 50,000 men and women aged 30-54 at baseline, elevated blood pressure was strongly related to cardiovascular and total mortality in both sexes. However, in men the mortality rates and relative risks were higher than in women. It was estimated that a reduction of 6 mmHg in diastolic blood pressure results in a 41% reduction in cardiovascular mortality and 28% reduction in total mortality for men and 29% and 12%, respectively, for women. Evidence from observational studies and intervention trials suggest that such a reduction may be achieved through preventive measures such as weight control, alcohol and salt restriction, and increased potassium intake.
Epidemiology of stroke : the role of blood pressure, alcohol and diet
Keli, S.O. - \ 1995
Agricultural University. Promotor(en): Daan Kromhout; Edith Feskens. - S.l. : Keli - ISBN 9789054854173 - 91
hersenziekten - vaatziekten - bloedstoornissen - hart- en vaatziekten - hart- en vaatstoornissen - bloeddruk - alcoholische dranken - voedselhygiëne - voedingstoestand - consumptiepatronen - preventieve geneeskunde - ziektepreventie - preventie - epidemieën - epidemiologie - nederland - nederlandse antillen - brain diseases - vascular diseases - blood disorders - cardiovascular diseases - cardiovascular disorders - blood pressure - alcoholic beverages - food hygiene - nutritional state - consumption patterns - preventive medicine - disease prevention - prevention - epidemics - epidemiology - netherlands - netherlands antilles
<p>This thesis evaluates the recent trends in stroke mortality in the Netherlands Antilles, and the role of long-term blood pressure, alcohol and diet as risk factors for stroke incidence. The official mortality statistics and population data from the Netherlands Antilles over the period 1981-1992 were used to study trends in stroke mortality. The association of long-term blood pressure, alcohol and diet were studied with data from the Zutphen Study, a longitudinal study on risk factors for chronic diseases in the Netherlands. Repeated blood pressure measurements were collected yearly between 1960 and 1970. Information on alcohol and diet was collected in 1960, 1965 and 1970 with the crosscheck dietary history method. Stroke incidence data were present for the period 1970-1985.<p>Age-adjusted stroke mortality declined over the period 1981-1986 in men and women in the Netherlands Antilles. Over the period 1987-1992 a slow down occurred in men, and in older women even an increase was observed. The average of individual repeated systolic blood pressure measurements over a period of 10 years was shown to be a better predictor of stroke incidence than single measurements. The latter understimated the stroke risk by 55%. Moderate alcohol consumption was associated with a nonsignificant 34% lower stroke risk. Consumption of one serving of fish per week was associated with a 50% lower stroke incidence compared with the consumption of less fish. Men with high intake of dietary flavonoids and men who drank their main source tea frequently had a 70% lower stroke incidence compared with men with a lower intake of flavonoids or tea. Men with high intake of beta-carotene had a 46% lower incidence of stroke, although this was not statistically significant. The effects of blood pressure, fish and flavonoids were independent from each other, and from other risk factors for stroke.<p>We conclude that the decrease in stroke mortality in the Netherlands Antilles came to a standstill, and that long-term blood pressure and diet are important predictors of stroke.
Effect of monounsaturated fatty acids on high-density and low-density lipoprotein cholesterol levels and blood pressure in healthy men and women
Mensink, R.P. - \ 1990
Agricultural University. Promotor(en): J.G.A.J. Hautvast; M.B. Katan. - S.l. : Mensink - 122
bloedvetten - lipoproteïnen - bloeddruk - bloedsomloop - effecten - oleïnezuur - onverzadigde vetzuren - carbonzuren - acrylzuur - voeding - cholesterol - blood lipids - lipoproteins - blood pressure - blood circulation - effects - oleic acid - unsaturated fatty acids - carboxylic acids - acrylic acid - nutrition
<TT>The purpose of the studies described in this thesis was to examine the effect of monounsaturated fatty acids on the distribution of serum cholesterol over high-density and low-density lipoproteins (HDL and LDL) and on blood pressure in healthy men and women. High levels of LDL cholesterol and blood pressure, and low levels of HDL cholesterol are associated with an increased risk for coronary heart disease.</TT><p><TT>Three controlled dietary studies were carried out. In the first study it was found that that monounsaturated fatty acids (oleic acid) specifically lowered non-HDL cholesterol when they replaced saturated fatty acids in the diet. In contrast, complex carbohydrates lowered both HDL and LDL cholesterol. The results of the second study indicated that it is immaterial whether saturated fatty acids in the diet are replaced by a mixture of monounsaturated and (n- 6)polyunsaturated fatty acids (oleic and linoleic acid) or by (n-6)polyunsaturated fatty acids alone. The two unsaturated-fat-rich diets had the same effect on HDL cholesterol and both lowered the level of LDL cholesterol to the same extent. In the third experiment we found that, when compared with <u>cis</u> monounsaturated fatty acids, <u>trans</u> monounsaturated fatty acids lower HDL cholesterol levels. In addition, <u>trans</u> fatty acids increased the level of LDL cholesterol, although to a lesser extent than did saturated fatty acids.</TT><p><TT>No effects of specific fatty acids on blood pressure were detected in any of the three experiments.</TT><p><TT>It is concluded that replacement of fats rich in saturated or <u>trans</u> fatty acids by oils rich oleic or linoleic acid might be helpful for the prevention of coronary heart disease, as far as lipoprotein levels are concerned. Weight gain, however, might be an unwanted side-effect of such high-oil diets.</TT><p><TT></TT>