In yesterday's post we saw how the real sport, in the sense of "racing", is actually harmful to health and what should be the ultimate goal of any physical activity: physical, mental and social well-being, health-oriented and prevention. . . Today
touch another hot topic that concerns the world of nutritional supplement products, as anticipated yesterday, increasingly complex and diverse and is becoming more and more powerfully in the world of fitness and wellness, taking with him all his wealth of misinformation and misconceptions and a booming market.
you think is really so far the integration Food from the reckless use of drugs? Maybe yes, maybe no, the fact is that the current sport psychology tends to define this behavior as a kind of behavioral psychology related to the philosophy of doping, "and always take food supplements to improve their performance and style of life.
The document will explain later was drafted by a set of associations for the protection of consumers, by an expert in public health and an expert in health education, its purpose is just to point out the potential danger related reckless use of dietary supplements.
My advice is that dietary supplementation andrebbe effettuata solo sotto controllo medico e dopo adeguate ed approfondite analisi del sangue che ne determinino le effettive carenze e il possibile impatto che queste possono avere nell'attività sportiva e nella vita di tutti i giorni.
Da professionista delle scienze motorie tendo a sconsigliare l'utilizzo di questi prodotti.
Personalmente sarei più propenso a seguire le indicazioni del prof. Umberto Veronesi per una vita sana: non fumare, praticare una regolare attività fisica, bere molta acqua (quella del rubinetto va benissimo) e seguire una dieta sana mangiando molta frutta e verdura.
Ecco a voi un approfondimento sui recenti studi riguardanti il mondo degli integratori alimentari e i rischi ad esso correlati:
Summary . The preparations
antioxidant vitamins - such as vitamins A, E, beta carotene
- cronicodegenerative
protect against disease (and not do damage
)? Unfortunately not
. There is strong evidence that pharmacological doses
,
not be reached with a healthy diet, and can not protect
increase mortality. The abuse of antioxidant vitamin preparations
is a problem not to be overlooked.
In the United States 35% of adults and elderly
take multivitamin supplements, in Italy about 10% of seniors said
use by 'several times per month "to" daily ", but such practices are not mass
supported by scientific evidence.
Take for example the vitamin (vitamin) E. Since that contained in food have antioxidant action
, many studies have used vitamin supplements. And to prevent chronic diseases
, but the results were disappointing. Three recent analysis of clinical trials have not
found no effect on survival, but several studies have reported high-dose increases
trend of total mortality and a study of over 9000 patients with cardiovascular disease or diabetes
followed for 7 years showed a
a significant increase of heart failure (+13%) and hospitalizations due to heart (+21%).
Miller's research on the prestigious journal JAMA has published a systematic search with
combined analysis of all valid studies (called randomized controlled trials)
with at least one year duration and reported that the total mortality, which is a clinically important indicator
indisputable and not subject to possible misinterpretation.
The study included 19 randomized controlled trials with nearly 136,000 participants and 12,500 deaths
, trust is very high and the results are solid.
various doses of vitamin used. It is expressed in units internazionali al giorno (UI) e coprono
tutti i livelli possibili, da 16,5 a 2000 UI, con un valore mediano di 400 UI.
La ricerca ha avuto un finanziamento della casa farmaceutica Roche, che produce vitamine:
ciò rende ancor più credibili le conclusioni, che non sono state certo a favore dei
supplementi vitaminici, come si vedrà.
Risultati
La mortalità totale per dosi minori di 400 UI al giorno non è aumentata, mentre per
dosi uguali o maggiori di 400 UI l’aumento è stato del 4%, statisticamente
significativo. L’analisi delle risposte in relazione alle dosi mostra un aumento di rischio
abbastanza regolare con l’aumento di dose oltre 150 UI (che
is practically the maximum he could get a diet alone), without differences by sex, age or duration
recruitment in several studies. Concomitant use of other vitamin supplements in addition to
vit. Slightly increased mortality.
The results can be extended at least to all persons similar to those studied (ie
adults and the elderly with cardiovascular risk factors or chronic diseases), which are also those where the consumption of vitamin preparations. It is the greatest. In addition, the duration of intake of vitamin
. And in the studies was considered significant (up to over 8 years, with an average of almost
5) and the effect was consistent in different studies with the dose used.
Conclusions
vitamin supplements. And, especially when taken in high doses, may be associated with
multiple deleterious effects, including increased oxidation and increased aging
tissue (ie the opposite of the effects achieved with physiological doses of this vitamin
) and anticoagulant effects.
doses equal to or greater than 400 IU per day of vitamin E are associated with increased mortality
total.
Comment
The damaging effects of medium and high doses of vit. It is even more unacceptable because
do not protect against certain chronic diseases for which
have been proposed as dementia and macular degeneration of the retina
of age, and increase the severity of acute respiratory infections in elderly
.
In a large representative sample of the adult population in the United States consumption of vitamin
median. And with diet alone was 9 IU (with a maximum range of variation
from 0.04 to 183 IU), while 11, 3% of Americans used supplements
with at least 400 IU, ie levels that expose a increase in overall mortality.
In Italy the official value recommended by the RDAs 3 is about 12 IU, but it is recommended
to increase it to a higher consumption of polyunsaturated fats (which is actually good
increase species for the valuable omega-3 4.
fats or lipids are divided into saturated •
are harmful to the arteries and raise blood cholesterol.
are prevalent in animal fats, especially meat
of cattle and ruminants in general and in milk and dairy products, especially in
butter and cream cheese, as well as in some vegetable oils such as palm or
especially coconut. Cholesterol,
however, is not only synthesized in the body, but
can also be introduced directly through the
foods of animal origin (those not containing vegetable instead
).
• Monounsaturated: do not harm the arteries and do not change
the level of cholesterol in the blood. They are found in many foods and plants
in olive oil.
• Polyunsaturated: lower cholesterol, particularly if used
along with a diet rich in fiber and tend to
reduce cardiovascular risk. Contains
especially in food plants and seed oils;
in the latter form, however, are very vulnerable to oxidative damage in the event of
heating and prolonged storage in air (with very unfavorable changes in oil
reused for frying) . In addition, the seed oils should not be
a large excess in relation to sources of omega-3 fatty acids
.
Fish is the exception between animal foods, having a high
omega-3 fatty acids, particularly polyunsaturated
protection. These are also formed based on acid alpha-linolenic
fat, contained primarily in flaxseed and walnuts, but also in
other nuts and oil in soybean.
• trans: derived from fatty acids and industrially processed
abound in margarines, especially those in solids, while in nature are present only in trace
. They are also found in many cookies and baked goods where the labels speak
hydrogenated vegetable fats and are present in large amounts in the oils used for frying
in most restaurants and fast food chains. They increase the
colesterolo LDL o colesterolo cattivo
e diminuiscono quello buono o HDL: favoriscono
dunque l’aterosclerosi, come e più dei grassi saturi,
sono associati allo sviluppo di alcuni tumori, alla resistenza
all’insulina e al diabete.
Per evitare queste e altre sostanze non desiderabili è indispensabile
abituarsi a leggere le etichette e, per il
pane e i piatti comprati al banco, leggere gli
ingredienti, esposti per legge in ordine decrescente
di quantità su cartelli visibili.
La prescrizione di cibi opportuni può coprire ogni fabbisogno di vit. E,
mentre la prescrizione di vit. E in farmaci a pazienti con malattie cardiovascolari e croniche
non ha più justifications.
The increase in mortality with vitamin preparations
, however, is not only the victims
. E.
antioxidant cocktail (vitamin E + C +
beta-carotene) 20,500
in adults with diabetes or cardiovascular risk have given away a 5-year trend
increased total mortality, vascular and cancer, and more hospitalizations for bronchitis
or chronic asthma. A combined analysis of studies on beta-carotene in cardiovascular protection
5 showed a slight increase in mortality.
A combined analysis of 14 trials with these vitamins + VIT. A
for the prevention of gastrointestinal cancers
6 did not show any protection, even a higher mortality of 6% in 7 studies
better, that the authors
would mean around 9,000 premature deaths per million persons
users.
In particular beta-carotene + Vit. A
have increased mortality by 29%, and beta carotene
+ vit. And 10%.
was published in 2007 7
larger version of this combined analysis, which included 68 randomized controlled studies
, with 233,000 participants. When the authors focused on 47 studies
better,
considered a lower risk of error according to the assessment criteria more stringent, the antioxidant supplements increased the
5% lamortalità general, statistically significant, and in particular the
vit. A 16%, beta-carotene by 7% and vit. And 4%. Vitamin
. C and selenium did not show significant increases in mortality, but not reductions
and their role should be investigated first to propose the wide use of fact that we are witnessing today
. Prolonged selenium supplements may help with diabetes.
The authors stress the 7-esteem of thousands of excess deaths for every million people who take vitamin preparations for about 3 years
antioxidants at doses commonly used by the populations studied (on average, every day or every other day, 18 mg the
beta-carotene, 20,000 IU for the victims. A, 570 IU for vitamin. E, 490 mg for the vitamin. C and 99 micrograms for selenium
: compare with Appendix). In addition, the authors
conclusions are particularly robust, since it is one of the subjects studied
more and better in health. What's more, the trend has been well demonstrated to publish the results
less favorable to the interventions and medicines that are tested in clinical trials
, because sponsors typically have less reason to disseminate information
unfavorable to their products. Therefore the authors of this great
review of published studies on the relationship between antioxidant vitamins and mortality consider that their conclusions can already be so alarming
even optimistic than the reality.
Indeed, the increase in lung cancer and mortality in smokers and workers exposed to asbestos
treated with beta-carotene and vit. A has been known for over a decade. Several studies
supplements beta-carotene also showed an increased risk of prostate cancer
and adenomas or benign tumors of the large intestine (which may be precursors of colon cancer
). The accumulation of negative evidence has led the AIFA (Italian Drug Agency
, which operates within guidelines and under the supervision of the Ministry of Health
) to require manufacturers of medicinal products that use beta-carotene
as excipients (ie inactive as a vehicle) to replace or reduce it: the amount acceptable daily
introduced through such products must be less than 2 mg.
The use of vitamin supplements. A is also associated with an increased risk of hip fractures. So
integration with vitamin preparations
a population that is not in terms of the shortage has always
total adverse effects?
could be a matter of dose.
fact, a recent French study in healthy adults
followed for 7.5 years showed a reduction of mortality
Total and cancer in males with
a capsule with low doses of vit. C + + E + beta-carotene
selenium and zinc, but it was
doses
not different from those obtained with
a healthy diet. This seems to confirm that the amounts of antioxidants are healthy
those achievable with a diet rich in fresh fruit and dried fruit oil, vegetables, whole grains
, and that we should prescribe this drug
power rather than supplements.
More generally, outside of deficiencies documented, there are valid reasons why
large segments of the population take vitamin preparations, with few exceptions such as folic acid
for women attempting to conceive, the vit. B12 for the elderly with atrophic gastritis and
vit. D (which deserves separate treatment). But even in these cases, excessive doses
are no risks.
Today millions of Italians make use of medicines based on vitamins, with private spending
of € 150 million (plus another million to be paid by the National Health Service)
largely unjustified. Be aware of the risks (so far underestimated)
indiscriminate and prolonged intake of these drugs, especially if the doses are clearly higher than those achievable by
nutrition, and choose healthier alternatives.
Bibliography (1) Lonn E et al. Effects of long term vit. E supplementation on cardiovascular events and
cancer: a RCT [HOPE and HOPE TOO]. JAMA 2005;
293:1338 (2) Miller ER III et al. Meta-analysis: high dosage vitamin E supplementation May INCREASE
all-cause mortality. Ann Intern Med 2005; 142:37
(3) levels of recommended intakes of energy and nutrients for the Italian population.
Italian Society of Human Nutrition, 1996
(4) A. Donzelli The omega-3 fatty acids. Why should I eat fish (or nuts, or soy ...).
pill health education No.11, September 2005
(5) Vivekananthan DP et al. Use of antioxidant vitamins for the prevention of CV disease :
meta-analysis of RCT. Lancet 2003; 361:2017
(6) Bjelakovic G et al. Antioxidants supplements for prevention of gastrointestinal cancers:
a systematic review and meta-analysis. Lancet 2004; 364:1219
(7) Bjelakovic G et al. Mortality in Randomized trials of antioxidant supplements for primary
and secondary prevention. Systematic review and meta-analysis. JAMA 2007; 297:842
(8) Stranges S et al. Effects of long-term selenium supplementation on the incidence of
type 2 diabetes. Ann Intern Med 2007; 147:217
Per ulteriori approfondimenti si rimanda al link: http://www.acu.it/progetti/consumatori_e_mercato/preparati%20vitaminici.pdf
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