Eat less — and live to ?

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Eat less — and live to 130

by Mattin

Calorie restriction prolongs the life of rats but can it do the same

for us?

Breakfast for Dave Fisher is always a single egg white. Even that he

eats reluctantly, but does so to avoid taking his daily vitamin and

mineral supplements — six capsules in all — on an empty stomach. Lunch

and dinner, too, are carefully monitored: with superhuman discipline

Fisher sticks to an intake of 1,600 calories a day, well below the

2,550 that the British Nutrition Foundation recommends for men. But

Fisher doesn't want to lose weight. Even when he started eating this

way, 16 years ago, he had no excess pounds to shed.

Rather, he's a dedicated practitioner of the controversial food

programme known as " calorie restriction " (CR). Followers of the CR

diet insist that by cutting back on calories, sometimes by up to 40

per cent of recommended levels (about as low as you can go before

risking muscle wastage), they can slow the ageing process, as if

putting their bodies into biological slow-motion. Some practitioners

of CR confidently expect to live to 130. After all, they claim, theirs

is " the only scientifically proven life-extension method known to

modern science " .

That science dates back to 1935 when Professor Clive McKay, of Cornell

University biology department, discovered that rats on a restricted

calorie intake appeared to age more slowly, and live up to 50 per cent

longer, than counterparts left to eat as they pleased. The same

phenomenon has been observed in many scientific trials since then in

mice, worms and dogs, and others. Fisher, 48, who owns a recruitment

agency, started to investigate CR in 1989, when he read about one of

those trials.

At the National Institute of Ageing, in Baltimore, Dr Mark Mattson is

conducting the first major study into the long-term effects of meal

skipping in humans. However, there is no research yet to demonstrate

that CR works in humans, and there is concern that people who

drastically reduce calorific intake risk deficiencies in vital nutrients.

Fisher decided to make changes to his lifestyle anyway, first

eliminating confectionery and wheat and scaling down portion sizes.

" As a child I always thought that, far in the future, ageing would be

cured, " he says. " But this is something I can do today. All the

science shows that CR works. "

At 5ft 10in (1.78m), his weight dropped from around 11st to 9½st (70kg

to 56kg). " I looked gaunt and bony, " he recalls, " and I was hungry.

Although I was eating less, I was still eating poor foods. " CR is not

just a case of less food. The mantra is " calorie restriction with

optimum nutrition " : the idea being that because practitioners aren't

eating a lot, anything they do eat must be packed with vitamins and

minerals in order to avoid deficiencies.

A typical lunch for Fisher might be strips of chicken breast, prawns,

a packet of blueberries, raspberries or beans, and a couple of dates.

It sounds a lot, but to stick to 600 calories, he'll often eat just a

bit of each packet and throw away the rest. Dinner: perhaps prawns

with chilli, then watermelon. Pasta and potatoes (high energy, but

apparently not so nutrient-packed) are out. As are beef, pork, lamb

and dairy. And no alcohol. On this regime, his weight has risen to

10st 11lb. That puts his body mass index (the indicator of ideal

weight for a given height) at 20.8, at the lower end of the

recommended range (18.5-25).

" I'm never hungry. I feel full of energy. Sometimes if I smell

doughnuts, I might fancy one. But I'd never eat one. "

CR can be expensive — Fisher spends £15 on lunch each day — and there

are side-effects: CR dieters tend to get cold even in summer: " My body

isn't wasting calories making excess heat, " Fisher says. Still, as far

as he is concerned, CR is working. Two years ago he went to Washington

University to take part in a continuing study of CR in humans, and a

fitness test placed him in the top 10 per cent of the population for

cardiovascular health, despite the fact that his energy intake means

he can't do much exercise. Other tests — body fat, cholesterol —

indicated a man two decades his junior.

The Washington University trials were set up in 2002 and involve about

30 participants. Dr Luigi Fontana, clinical investigator, says CR

practitioners seem to be ageing more slowly than the rest of us. " Take

systolic blood pressure, " he says. " Usually, that rises with age

reliably, partly because the arteries are hardening. In my group, mean

age is 55, and mean systolic blood pressure is 110: that's at the

level of a 20-year-old.

" Of course, I can't tell you if my subjects will live to 130. So many

uncontrollable factors affect length of life. I don't have enough

evidence to prove these people are ageing more slowly, but it looks

like it. "

Yet despite this, Fontana doesn't follow CR himself: " I eat a healthy

diet, but I don't want to become fanatical about counting calories.

Nutrition is just as important: I try to eat foods that are high in

nutrients and low in calories, such as fruit, and avoid high-calorie,

low-nutrient foods such as white bread. "

The Washington study finds many of its subjects through the world's

biggest organisation for followers of CR: the Calorie Restriction

Society, in California. The society was founded in the early 1990s by

Delaney, an academic, and Roy Walford, author of the CR

follower's bible The 120-Year Diet. Walford was Professor of Pathology

at the UCLA School of Medicine, and CR's best-known advocate. He

followed the diet himself, but died last year of motor neurone

disease, aged 79. At the CR Society website —

www.calorierestriction.org — followers swap recipes and discuss the

latest research.

" I'm surprised that more people don't know about CR, " says Delaney, 42

(top left) who at 5ft 11in say he is " not scrawny " at 10st (BMI: 19.52).

" Part of the problem is that it's often presented as an all-or-nothing

choice. Sure, we have members who cut back to 1,100 calories and hope

to live to 150. But the science suggests that if you restrict calories

a bit, you'll age a bit more slowly. You don't have to do the extreme

version. "

Still, Delaney, who says the society membership of around 1,600 is

" overwhelmingly male " , concedes that no one is yet sure of just how,

exactly, CR might work. " The truth is, we still aren't sure how CR

slows ageing in rodents, " says Dr Merry, a reader in biosciences

at Liverpool University. " In CR, cells seem to produce damaging free

radicals at a reduced rate. But we aren't lab mice: it will take

decades of further research to discover whether CR slows ageing in

humans. "

He does point, though, to key anecdotal evidence. The inhabitants of

the Okinawa islet of Japan, for instance, are known for their

low-calorie diet — lots of fish, soy, and wholegrain rice — that

crucially, and unlike most naturally occurring low-energy diets, is

packed with nutrients. They also have the highest proportion of

centenarians documented in any population: more than 600 in around 1.3

million. But Dr Merry says that he won't try CR: " The evidence isn 't

good enough, and there are too many downsides. "

Dr Shrimpton, a retired consultant on nutrition to the

government and independent advice body the Health Supplements

Information Service, suggests CR practitioners " are on a knife edge " .

" Unless they balance their diet exactly, they are in danger of

becoming deficient in vital amino acids, in vitamins C and D, in

selenium and zinc. Unless your body gets enough energy, you'll suffer

muscle wastage and feel tired all the time. No one has yet done CR for

a lifetime, so who knows whether it's safe, or if it works? Even if it

does, most people wouldn't be satisfied with such a monastic existence. "

For those seeking a long and healthy life, Shrimpton offers

traditional advice: " Get your weight at the lower end of the

recommended levels and keep it. Eat a varied diet, with lots of fresh

fruit and vegetables. "

But for Dave Fisher, this line doesn't promise enough. " No one wants

to die now. So why think you'll feel different at 80? I want the extra

years CR can offer. If I get to 110, then they may have tools that

will fix ageing. A kind of rejuvenation procedure, " he says. " People

may call me obsessive, but this is logical behaviour. "