2.1. Utrzymanie prawidłowego stężenia cholesterolu we krwi (ID 493)

The claimed effect is “blood cholesterol”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effect relates to the maintenance of normal blood cholesterol concentrations.
Low-density lipoproteins (LDL) carry cholesterol from the liver to peripheral tissues, including the arteries. Elevated LDL-cholesterol, by convention >160 mg/dL, may compromise the normal structure and function of the arteries.
The Panel considers that the maintenance of normal blood cholesterol concentrations is beneficial to human health.

2.2. Utrzymanie prawidłowego ciśnienia tętniczego (ID 625)

The claimed effect is “blood pressure”. The Panel assumes the target population is the general population.
In the context of the proposed wording, the Panel notes that the claimed effect relates to the maintenance of normal blood pressure.
Blood pressure (BP) is the pressure (for per unit area) exerted by circulating blood on the walls of
blood vessels. Elevated BP, by convention 140 mmHg (systolic) and/or 90 mmHg (diastolic), may compromise the normal function of the arteries.
The Panel considers that the maintenance of normal blood pressure is beneficial to human health.

3.1. Utrzymanie prawidłowego stężenia cholesterolu we krwi (ID 493)

Clinical trials comparing the effects of different vegetable oils on serum lipids in normolipidaemic subjects have shown that the effect of alpha-linolenic acid (ALA) on serum cholesterol is similar to that of linoleic acid (LA) (Mantzioris et al., 1994; Valsta et al., 1995; Pand et al., 1998). In a meta- analysis of 60 randomised controlled clinical trials, the replacement of 1% of energy from carbohydrates by polyunsaturated fatty acids (PUFA), mainly as LA, reduced serum LDL cholesterol levels by 0.02 mmol/l (Mensink et al., 2003). The estimated change in the total to HDL cholesterol
ratio was -0.032. Although LA was the main source of PUFA in the studies above, smaller amounts of ALA were also used in some of the studies. Moreover, as indicated in the studies by Mantzioris et al. (1994), Valsta et al. (1995) and Pand et al. (1998), the effects of LA and ALA on serum lipoproteins are similar and the n-6/n-3 ratio of dietary PUFA does not affect the serum lipid profile (Goyens and Mensink, 2005).
No specific data on the effects of ALA intake on cholesterol levels have been presented for children, but there is no scientific evidence for different effects in children as compared to adults.
The Panel considers that a cause and effect relationship has been established between the dietary intake of ALA and the reduction of blood cholesterol concentrations.

3.2. Utrzymanie prawidłowego ciśnienia tętniczego (ID 625)

The consolidated list provided 13 references for the substantiation of this claim. Three references were considered as not pertinent for substantiation of the claim (Abeywardena et al., 2001; Geleijnse et al., 2002; WHO, 2003), as the reports were focussed on long chain-PUFA (LC-PUFA) from marine sources (mainly eicosapentaenoic acid and docosahexaenoic acid). Two general reviews are also excluded as they did not examine the relationship between ALA intake and blood pressure (BP) (Wijendran and Hayes, 2004; Stark et al., 2008).
A systematic review by Wendland et al. (2006) included three RCTs which investigated the effects of ALA intake on BP and concluded that systolic and diastolic BP are not affected by ALA intake (Bemelmans et al., 2002; Finnegan et al., 2003; Kestin et al., 1990). The 2-year randomised study with parallel design by Bemelmans et al. (2002) compared the effect of daily supplementation with ALA-enriched margarine (total daily ALA 6.3 g and LA 26 g, n=96) with that of unenriched margarine (total daily ALA 1 g and LA 27 g, n=141) on BP in middle-aged men and women at risk of cardiovascular disease. The 4-month double-blind, randomised, placebo-controlled study with parallel
design by Finnegan et al., (2003) compared the effect of daily supplementation with ALA-enriched margarine (total daily ALA 4.5 g and LA 16 g, n=29, or total daily ALA 9.5 g and LA 13 g, n=29)
with that of unenriched margarine (total daily ALA 1.5 g and LA 23 g, n=29) on BP in moderately
hyperlipidaemic adults. The 6-week double-blind, randomised, placebo-controlled study with
parallel design by Kestin et al., (1990) compared the effect of daily supplementation with ALA (9 g provided as linseed oil, n=11) in place of an equivalent amount of LA (9 g provided as safflower oil, n=11) on blood pressure in normotensive and mildly hypercholesterolemic men. All three studies found no significant differences in systolic BP or diastolic BP between the ALA intervention group and the control group.
Four randomised controlled intervention studies were also provided (Takeuchi et al., 2007; Paschos et al., 2007; Sioen et al., unpublished; Vuksan et al., 2007).
In a randomised controlled study in subjects with normal BP, high-normal BP or mild hypertension consuming a test diet containing 3.4 g/d ALA (flax oil and rice oil in bread rolls), systolic BP was significantly lower (~ - 4 mmHg) after 4, 8 and 12 weeks in the test group (n=58) than in the control group (n=53) consuming a diet containing 1.7 g/d ALA (equivalent amount of rapeseed and soybean oils in bread rolls) and returned to control BP values 4 weeks after cessation of the intervention. A significant decrease in diastolic BP (~ -3 mm Hg) was observed only at week 12 in the intervention group compared to controls (Takeuchi et al., 2007).
The 12-week study with parallel design by Paschos et al. (2007) compared the effect of daily supplementation with flaxseed oil (15 ml providing 8 g ALA and 2 g LA, n=59) with safflower oil (15 ml providing 0.1 g ALA and 11 g LA, n=28) on BP in middle-aged dyslipidaemic men. Background diets of the two groups had similar quantities of ALA (1g/d) and total PUFA (12 g/d). After 12 weeks,
a median decrease of 3% in systolic BP and of 6% in diastolic BP was observed (median decrease around -5 mm Hg) in the intervention group compared to controls.
In an unpublished paper (Sioen et al.), a 12-week study compared the effect of substitution of common foods with their naturally ALA-enriched counterparts (to provide 5 g/d ALA, 18 g LA vs 2.8 g/d ALA, 18 g LA in controls) in 48 middle-aged men. It is unspecified how many subjects per group completed the intervention. No effect of the test diet was observed on systolic BP, whereas a significant -3 mm Hg decrease was measured for diastolic BP compared to the control diet.
A 12-week study with single-blind cross-over design (Vuksan et al., 2007) was performed on 27 type II diabetic subjects on conventional anti-diabetic therapy using 34 g of whole grain in a ground form or as bread (Salvia hispanica L.) providing 7.4 ± 4.3 g/day ALA compared with 1.1 ± 0.8 g/day ALA in the control diet (same amount of wheat bran) . A 6 mm Hg reduction in systolic BP was observed with the intervention diet as compared to the control diet. The Panel considers that the evidence provided does not establish that results from this study on type II diabetic subjects on conventional anti-diabetic therapy can be extrapolated to the general population.
Two observational studies were presented. In a cross-sectional study of 4594 adults (Djousse et al., 2005), intake of ALA in consecutive quartiles was on average 0.4, 0.6, 0.8 and 1.2 g per day. Prevalence odds ratios for hypertension (with 95% CI) were 1.0, 0.72 (0.56 to 0.93), 0.70 (0.52 to 0.93), and 0.66 (0.49 to 0.94), from the lowest to the highest quartile of ALA intake. The dietary intake of ALA was also associated with a lower resting systolic BP ( 2.0 mm Hg difference between highest and the lowest quartiles of ALA), but not with diastolic BP. In an international cross-sectional epidemiological study in 17 population sub-groups (Ueshima et al., 2007), a small inverse association was observed between ALA intakes and systolic BP (in the range of -0.5 to -1 mmHg).
An animal study in spontaneously hypertensive rats (Sekine et al., 2007) compared the acute (after 4 hours) effect on systolic BP of administration of 1 ml flaxseed oil and 1 ml of high oleic safflower oil. The Panel considers that evidence provided does not establish that evidence derived from this animal model can be extrapolated to effects on blood pressure in humans.
In weighing the evidence the Panel took into account that the observed effects of ALA intake on BP in the human intervention studies were inconsistent, the lack of evidence in these studies, that the study design, including sample size, was appropriate to demonstrate an effect of ALA alone on BP, that cross-sectional studies have considerable limitations as a source of evidence for the claim, and the lack of evidence for a plausible mechanism for the claimed effect.
The Panel concludes that the evidence provided is insufficient to establish a cause and effect relationship between the dietary intake of ALA and the maintenance of normal blood pressure.

4.1. Utrzymanie prawidłowego stężenia cholesterolu we krwi (ID 493)

The Panel considers that the following wording reflects the scientific evidence: “Alpha-linolenic acid contributes to maintenance of normal blood cholesterol concentrations”.

5.1. Utrzymanie prawidłowego stężenia cholesterolu we krwi (ID 493)

In order to bear the claim a food should contain at least 15% of the proposed labelling reference intake value of 2 g ALA per day. Such an amount can be easily consumed as part of a balanced diet. The target population is the general population.