198
J.G. Bell and R. Waagbø
animal and human studies (Storlien et al. 1998; Lombardo and Chicco 2006). In
inflammatory conditions of the bowel, consumption of oily fish reduced relapses in
patients with Crohn’s disease (Belluzzi and Miglio 1998) and in ulcerative colitis,
dependence on steroids was reduced as well as improved colon histology following
supplementation with n-3 HUFA (Rogers 1998). In a study with patients suffering
from Crohn’s or ulcerative colitis, reduced disease activity, serum cholesterol and
joint pain index were observed when patients were given an infusion of seal oil
(Arslan et al. 2002). In patients with the inflammatory skin condition, psoriasis,
improvements in itching, scaling, lesion thickness and erythema were observed
following supplementation with EPA + DHA (Ziboh 1998). In childhood asthma,
increased dietary n-3 HUFA tended to reduce the asthma severity, while increased
n-6 PUFA had the opposite effect (Hodge et al. 1996; Haby et al. 2001). However,
supplementation studies gave mixed results with some individuals reporting no
effects, while other reported reduced symptoms (Broughton et al. 1997; Hodge
et al. 1998). Another inflammatory condition that shows potential for response to
n-3 HUFA supplementation is cystic fibrosis, where low blood DHA levels have
been found (Roulet et al. 1997).
The proliferation of certain tumour cells is known to be increased by ARA,
while this effect can be reversed by inhibitors of eicosanoid production (Horrocks
and Yeo 1999). Subsequently, administration of n-3 HUFA has been shown to
promote programmed cell death (apoptosis) in leukaemia and lymphoma cell
cultures as well as in animal models (Fernandes et al. 1996; Heimli et al. 2002). In
addition, animal studies have demonstrated that consumption of n-3 HUFA can
reduce cancer growth rates, increase the efficacy of chemotherapy and reduce
associated side effects of treatment and of the cancer (Hardman 2002; Hardman
et al. 2002). The proposed mechanisms involve suppression of nuclear factor-κB
activation and alteration in expression of specific genes including suppression of
30
40
50
60
70
80
90
100
0
200
r
2 = 0.986
Greenland
Japan
Quebec Inuit
Quebec Cree
Quebec all
USA
% n-6 HUFA in Total HUFA
CHD mortality rate
Fig. 6.2 Coronary heart disease (CHD) mortality rates versus tissue n-6 HUFA concentrations in
subjects from the USA, Japan, Greenland, Quebec total population, Quebec Inuit and Quebec
Cree populations (Lands, 2002)
J.G. Bell and R. Waagbø
animal and human studies (Storlien et al. 1998; Lombardo and Chicco 2006). In
inflammatory conditions of the bowel, consumption of oily fish reduced relapses in
patients with Crohn’s disease (Belluzzi and Miglio 1998) and in ulcerative colitis,
dependence on steroids was reduced as well as improved colon histology following
supplementation with n-3 HUFA (Rogers 1998). In a study with patients suffering
from Crohn’s or ulcerative colitis, reduced disease activity, serum cholesterol and
joint pain index were observed when patients were given an infusion of seal oil
(Arslan et al. 2002). In patients with the inflammatory skin condition, psoriasis,
improvements in itching, scaling, lesion thickness and erythema were observed
following supplementation with EPA + DHA (Ziboh 1998). In childhood asthma,
increased dietary n-3 HUFA tended to reduce the asthma severity, while increased
n-6 PUFA had the opposite effect (Hodge et al. 1996; Haby et al. 2001). However,
supplementation studies gave mixed results with some individuals reporting no
effects, while other reported reduced symptoms (Broughton et al. 1997; Hodge
et al. 1998). Another inflammatory condition that shows potential for response to
n-3 HUFA supplementation is cystic fibrosis, where low blood DHA levels have
been found (Roulet et al. 1997).
The proliferation of certain tumour cells is known to be increased by ARA,
while this effect can be reversed by inhibitors of eicosanoid production (Horrocks
and Yeo 1999). Subsequently, administration of n-3 HUFA has been shown to
promote programmed cell death (apoptosis) in leukaemia and lymphoma cell
cultures as well as in animal models (Fernandes et al. 1996; Heimli et al. 2002). In
addition, animal studies have demonstrated that consumption of n-3 HUFA can
reduce cancer growth rates, increase the efficacy of chemotherapy and reduce
associated side effects of treatment and of the cancer (Hardman 2002; Hardman
et al. 2002). The proposed mechanisms involve suppression of nuclear factor-κB
activation and alteration in expression of specific genes including suppression of
30
40
50
60
70
80
90
100
0
200
r
2 = 0.986
Greenland
Japan
Quebec Inuit
Quebec Cree
Quebec all
USA
% n-6 HUFA in Total HUFA
CHD mortality rate
Fig. 6.2 Coronary heart disease (CHD) mortality rates versus tissue n-6 HUFA concentrations in
subjects from the USA, Japan, Greenland, Quebec total population, Quebec Inuit and Quebec
Cree populations (Lands, 2002)