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Once their simplistic and marketable narrative gets into the public consciousness it is hard to correct. Mike Callahan August 15, at 4: Wilbur February 5, at 8: Broth adds minimal calories and no fat, but gives a great taste and some moisture. I consider myself fairly athletic and I eat a gluten-free vegan diet.
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Several studies have confirmed that a pessimistic style of explaining bad events saying, "It's my responsibility, it's going to last, and it's going to undermine everything" makes illness more likely.
We see in the above examples that stress is the emotional factor relevant in most of psychoimmunology. It has already been found that those with bad stress responses are more likely over the long term to suffer from ill health. Those subjects who showed emotional stability and controlled responses to stress as adolescents had far better health at age 50 than did those subjects who had poor stress reactions when young.
Even if such practices did nothing at all about the underlying organic causes of illness, they nevertheless help people to manage their symptoms, and they give people a sense of control over their illness - a sense of control that might be tremendously beneficial even if it turns out to be illusory. Although this sounds good, it must be remembered that it is not the treatment itself that works. People are really being helped by psychotherapy - the time spent in personal reflection in an understanding environment, with nice and attentive practitioners.
In , Bertram Forer conducted a personality test, and then gave all of his students exactly the same personality profile, which he constructed from random horoscopes. This was occasionally previously known as the Barnum effect after a popularist entertainer. Extensive studies have found that this effect applies well to horoscopes, other astrological readings , messages given from the dead by spiritualists, various cold reading tricks and other profiling endeavours It is often mistaken for being a product of magical or supernatural means.
Lack of sociological sense and knowledge of cognitive errors and skeptical thinking methods leads some people to accept wild theories, based on misunderstandings of common experience. Freethought is healthy and appealing, but lack skeptical thinking also leads people into delusions and fantasies, and opens the doors for deception and consciously fraudulent practices, but most of all, for self-delusion. Their downfalls are often occasioned only slowly, as the evidence and careful checking , plus, having time to think, slowly results in a culture-wide change of opinion.
The most common thing that perpetuates these errors is believing in them based on personal testimonies. For example, many people argue that particular religions must be true because of how many other people believe in them 42 , Linked to this is many who chose to believe something because of the age of the belief Furthering such poor logic is a lack of understanding of statistical likelihood, and ignorance of thinking errors such as selection bias where we notice confirming evidence but ignore disconfirming evidence.
Because we instinctively value the popularity of a belief, our minds play a further trick on us: The basis of belief should be in the weight of evidence and not in a popularity contest. Practitioners themselves often exhibit the same credulity, allowing personal enthusiasm, pride and ego to completely obscure the need for scientific evidence.
He has been faced with sustained criticism from the scientific community for his claims about his sham products, but, rather than accept the evidence or fund proper trials of his stuff, he simply argues that "evidence-based medicine, at its worst, is exactly analogous to religious fundamentalism " 1.
Whilst it is true that fundamentalists are stubborn as can be, it also happens to be true that so is evidence. Amateur thinking, poor argumentation and misleading justifications for pseudo-scientific methods afflict both practitioners and patients.
It is an example of "pseudo-science", where scientific terms are used without genuine understanding of their meaning, but in a way that makes out-there theories look reasonable at first glance. Quantum Physics terminology and paraphernalia is often used as a basis for postulating how there might be 'souls' The eminent physicist Victor Stenger now deceased was a vocal critic of the abuse of quantum physics done by spiritualists of various kinds: Not surprisingly, this idea can be found in New Age periodicals and in many books on the metaphysical shelves of book stores" Aside from the "observer effect".
The Observe Effect and Quantum Entanglement are two the prime areas where non-scientific minds can often allow their imaginations to distort the science. However strange it may be, quantum physics is not a doorway to magic, even if peddlers of pseudoscience litter their works with scientific-sounding terminology.
St John's Wort has generally been found to be mildly effective as an antidepressant 1 , and, this chemical alone has been responsible for many of the positive findings of research into alternative medicines. It is not known as of how it works, although, it is only effective for everyday depression and not the severe and long-term forms of depression, for which proper medical assistance is required.
A statistical analysis of a few thousand Chinese studies saw it most frequently used to treat ischaemic heart disease, stroke, chronic viral hepatitis, peptic ulcers, childhood diarrhoea, hyperlipidaemia, primary hypertension, upper digestive tract bleeding, diabetes mellitus, and pneumonia At least 26 comprehensive scientific studies of acupuncture have shown that it has no significant effect.
But three large studies have found that acupuncture does reduce the incidence of headaches and migraines - although two of those have shown that sticking pins in randomly is as effective as using traditional Chinese methods. Scientists understand how the neural and hormonal stimulation of needles work in a biochemical way to sometimes produce the results of acupuncture.
What is known now is what has been suspected by practitioners for a long time: Instances of punctured lungs, increased pain, internal bleeding and other side-effects occur in up to 1 in 5 cases especially if a practitioner is not a medically trained doctor.
It works for pain relief for medically known reasons and also due to the placebo effect 49 , but the traditional mumbo-jumbo associated with traditional acupuncture is best ignored.
How Does it Work? Of particular importance for a person's whole life is their month of birth. Practices based on astrology include the production of horoscopes, prediction of imminent or medium-term events in people's lives. Belief in astrology has been in long-term decline in the developed world and it is opposed by most established organized religions 52 , but it is still a popular feature of many new religious movements 53 , 54 and astrological charts can still be found in almost every daily newspaper in the form of horoscopes One academic writes that " there can be few Western Europeans who do not know their zodiac sign " It is part of the underlying theory of the New Age 56 , 57 , and is very popular in India in particular, where it is institutionalized.
Astrological predictions have been tested scientifically and have been comprehensively found to be mistaken in both theoretical underpinning and practical application 58 , 59 , For example, David Voas looked at over ten million married couples and found absolutely no statistical effects relating to marriages between people of particular zodiac signs And Chinese astrology has a long history, but, they group the stars into completely different constellations and give prominence to the lunar mansions "a sign lunar zodiac" So it is clear that astrology isn't based on any particular sound theory.
Over the last years, the precession of the equinoxes has meant that each equinox and solstice point has moved around 30 degrees; an Aquarius today genuinely isn't the same sign as an Aquarius from history. Also, the dots that make up constellations are mostly stars, but many points are extremely distant galaxies, and the entire ensemble slowly moves and shifts over time, making most traditional methods of astrology useless Lack of knowledge of basic astronomy has made a mockery of astrology.
Also poor is their biology: Especially if you don't ask subjects how long they were in the womb for. The Forer Effect explains why most people readily accept that astrological descriptions are accurate - randomly assigned profiles are rated just as highly 63 , 64 , Astrological predictions of statistical likelihood of car crashes, divorces, etc, based on the month of birth nearly all fall foul of a simple statistical glitch - the Age Incidence Error Despite these problems, many continue to believe in astrology and horoscopes because general knowledge of statistical methods and general knowledge of thinking errors such as the Forer Effect is poor.
Also, it is popular because it is entertaining I am not going to attempt to explain how practitioners might possibly believe that this works, but the idea is that by sitting in an area where the lights are alternated between different colours, can somehow cure pretty much anything.
He is apparently completely oblivious to what light is and how it works, for such therapy is absolutely and completely meaningless, except perhaps for indirect psychological effects. There are many other colour cures for many - probably all - different maladies. Light combinations and patterns are completely made up by practitioners with absolutely no scientific basis, or evidence-base, to determine what colours to use for what ailments.
Because of the placebo effect some patients come to think it works at which point it can have serious consequences when patients choose to no longer seek genuine medical aid. For example, Ghadiali advised one diabetic father to stop taking insulin and accept the Colour Therapy instead, and unfortunately, he died 3 weeks later as a result Diet has an impact on health and affects the risk of disease Over the last few decades biochemical and other sciences, from neural to gastric, have made impressive contributions to our knowledge Never before have scientists known so much about food and nutrition.
Unfortunately much of this knowledge is not reported by the popular press and news outlets because it is technical, mundane and statistical in nature. The average consumer mostly hears only the sensational claims of pseudoscientific sham researchers and promoters, which are often paid for and orchestrated by the rich food industry itself.
The two most misleading sources of information are reports based on single-studies and TV adverts. Most people are ill-informed about diet and health as a result of this. There have been a long series of temporarily popular fad diets which limit food intake to a specific range of items, sometimes cutting out essential fats and proteins completely.
They emphasize rapid short-term change at the expense of medium and long-term issues. Of the independent scientific studies on fad diets, supplements, mega-vitamins and similar highly-hyped abnormal sources of nutrition, all have found them to be useless and sometimes actually harmful.
The National Health Service UK warns that "many fad diets are based on dodgy science or no research at all, prescribing eating practices that are unhealthy and can make you ill" The boring truth is that only well-rounded diets are truly effective at long-term weight management with only the very basic advice being effective: Fads rely on testimonials and public-relations tricks to make themselves sound effective and claims are often based on easily biased single-studies rather than on independently verified and duplicated scientific trials.
The mass media love reporting on these single-studies as their claims are often outlandish and celebrity endorsements boost a fad diet from time to time. Fad diets distract people from sensible eating habits.
Rather than accept enthusiastic praise from soap stars, models and newspaper advertisements, it is doctors and the medical profession that we should trust to keep us informed. Let's stop falling for these tricks! Herbalism is also called 'botanical sciences', 'herbalism' and 'herbal supplements'. It is the practice of preparing solutions from plants and administering them to patients.
Thus far, it sounds like much like many medicines. But there are extremely important differences between Herbalism and medicine:. Mainstream medicines are tested in a wide variety of conditions and are backed up with solid theory and large scale clinical trials. Herbalism does not follow the scientific route - its solutions are based on a practitioner's feel for their patient, the drugs have mostly not been tested scientifically and most doctors in nearly all developed countries avoid Herbal Remedies In the USA and in other countries, herbal remedies are marketed as dietary supplements because then they do not face any strict controls on their effectiveness or safety Because Herbal Remedies use whole plants, or parts of plants, they often contain a complicated mix of drugs and chemicals, and, remedies can contain up to 10 different extracts from such mixed sources.
Although it is biologically plausible that some of these have beneficial effects, the overall manner of application en masse is dangerous and there is little knowledge about what combination should be avoided, and what medical drugs that they interfere with. It is known that some Herbal Remedies cause additional risks. St John's Wort Hypericum perforatum is one of the few Herbal Remedies that has been tested scientifically, and it is known to have beneficial effects on those suffering from mild to moderate depression, as long as it is proscribed by a doctor and is carefully prepared.
Most Herbal Remedies are not carefully prepared. The American Society of Anesthesiologists warns that "the ingredients of herbal medications vary enormously from maker to maker, that potency and purity are inconsistent, and that product labels are not always accurate" Many Herbal Remedies have been found to interfere with formal medicines and so many side-effects have been experienced that doctors now have to routinely warn patients about the use of herbal remedies, and ask them if they have been taking any before they undergo any surgery.
Researchers at the University of Chicago in found that many patients do not disclose Herbal Remedies to doctors during pre-surgery surveys and as a result some of them suffer unexpected consequences, and the "American Society of Anesthesiologists has recognised the potential for adverse reactions and suggests that patients stop taking all herbal medications two weeks before surgery" Between and a total of 2, adverse reactions, including deaths, were reported to the United States Food and Drug Administration.
The conclusions of these studies is that homeopathy itself does not work 79 , 35 , 80 , 81 and only poorly controlled experiments are more likely to show that it works It is founded on confused and nonsensical ideas that have been proven to be false, and products can have unexpected side-effects The theory is that the water has "memory", that diluting the chemical makes the cure stronger , and that this memory is somehow what cures disease. The original solution is sometimes based on a "like cures like" principal, whereby a chemical that causes similar symptoms is used, and other potions are based on the same type of basic thinking as found in herbalism.
It works only by psychological side-effects 85 , and is akin to confidence-trickery, and as such Homeopathy works best on illnesses that have a strong psychological component, and on illnesses that come and go naturally no matter what interventions you make, like the common cold. Dr Ben Goldacre notes that " Homeopaths [ Because people do not understand concepts such as statistical regression most illnesses get worse then get better, all on their own nor the placebo effect the power of positive thinking on the body , many people are tricked into thinking that homeopathy works.
Your imagination is the limit. But, it works for most, and the weight loss can be dramatic. My friend has been doing the potato hack for months with great success but I have not fared as well.
The first time I tried it I became ill with indigestion and threw up. I assumed it was maybe a dodgy potato. Day 2 I ate nothing. Day 3 I tried a few boiled potatoes and started burping again. I reached out to my friend who is losing weight and feeling great for advice and he said his wife has had a similar experience to mine, that she has twice tried but has become sick on day one each time.
I wonder if you have any thoughts on the matter? I am generally healthy except for autoimmune thyroiditis and arthritis vegan middle aged woman. I have had great results with the master cleanse in the past.
Not that I lost weight on it but it seemed to reduce inflammation and reset my system somehow. Another reason I wanted to try this diet! I have never really been a meat eater. For years I was a mostly vegetarian.
I ate eggs and fish occasionally. But 17 years ago when I met my partner and he was vegan I transitioned. Well, then, it boggles my mind how a person could regularly eat potatoes, but a potato-only meal makes them ill. What happens if you eat a baked potato by itself?
Maybe try, but keep individual servings on the smaller side, ie. Hi Tim, day one here for me, I need to lose about 10kg, in Australia we go by kilos. I had grams dry fried potatoes with a little seasoned salt for late breakfast and grams of potoatoes cooked with low salt chicken stock in an oven roasting tin in the outside barbecue oven, 40 degrees Celsius here today so too hot to put the oven on in the house, I made three times that amount so enough for two more meals, will try dry roasted potato wedges in the barbecue tonight with just a pump spray of olive oil, maybe a tiny amount of tomato sauce and seasoned salt, I am looking forward to that, well day one and easy peasy so far though early days yet, thanks again.
Hi Tim, I figured I would post this since it may be the case with someone else too. After our exchange the other day I decided to give the potato hack another try day 2 today and again having problems which I realize are hypoglycemia.
Just to clarify, I am pounds so I am not doing this for weight loss but rather for fixing my gut, my skin problem and the recent flair of knee pain.
About 2 hours after my potato breakfast I feel lightheaded — both yesterday and today. I am paying specific attention to where this is coming from and it is not my stomach. I wonder if I should add that while potato hacking or take that first and then do the PH? Any feedback much appreciated. Do you have a tester? You can get an inexpensive one to see: No, I do not have a tester and never thought I needed one.
I never have this problem when eating a balanced meal. If I go get a tester, when should I be testing? That was my problem.
The only way to test this type is by continuous monitoring, a long test in which several sugars are given to induce the effect. Also, I had a bit if coconut oil with my lunch potatoes yesterday and today I had half an avocado with them and there was no more problem for the rest of the day. What I feel later is simple hunger. Wilbur, how did you know that yours was sensitivity to drops in blood sugar rather than hypoglycemia? Did you do continuous monitoring?
And also, how did you decide to take Glucomannan? Well, if you felt better adding some oil, then by all means keep it up! It sounds like you are on the right track, and if you get tired of potatoes add some sweet potatoes, plantains, beans, or lentils, too.
All good gut food. My entire life I knew it as hypoglycemia. It ran for generations in my family. And the test is arduous. I just took glucomannan because it was a fiber that was not already in my mix. I was trying to get lots of different fibers.
I just noticed that it went away entirely after starting glucomannan. And you will know it. I have never had bouts of dizziness when having a hypo episode. Sweating, jittery legs are other symptoms. And if you eat pure sugar it generally goes away quite quickly.
But it will spike your blood sugars again, sending them sky high again. If you generally have high blood sugar levels, then a big drop in sugar levels will give you the same signals of a hypo, when in fact your levels are still above normal.
That is because your body has accepted a higher set point and will give you the same symptoms when it drops below that set point. The only way to find out how your blood sugars are responding is by testing, which I have been doing for 15 years. I have recently found out that the condition of our gut flora has a huge influence on our blood sugars.
IPS, though, has the same symptoms without blood sugars being below the base level. The cause is unknown. Some people still call IPS hypoglycemia because the symptoms are the same. You can test for hypoglycemia because your blood sugar will be below the base level when it happens. For my former IPS, blood sugar would show normal when I had symptoms.
So testing for IPS seems to involve continuously monitoring to match onset of the symptoms to a drop in blood sugars. My understanding is that it is a five-hour test involving fasting and different types of sugars. Another difference is that IPS rarely never? As you know, true hypoglycemia can be very dangerous. And, yes, it is a very different type of hunger! From reading both your comments I think mine is something like what Wilbur describes and not what Jo describes.
Definitely not very severe. I have experienced it when out and about and never felt I was in danger. Just wanted to eat something sooner than I had planned. And it only happens between breakfast and lunch and not between lunch and dinner. I am going to try Glucomannan to see what effect it would have. I will probably get a blood tester kit too. The thing with glucomannan is that it swells a LOT. Karl the Elixa guy was astounded by how much. I think Tim has turned water into a brick with it.
I use about 20 oz. I would never, ever use capsules because of fear that one breaks in my throat. Both Karl and I experience a very full feeling while taking it. I take it with my other fibersbout 30 minutes after breakfast.
All sources I find recommend taking it 30 min before breakfast and you do the exact opposite. Can you share your reasoning? I take it every day. Is there any way to prevent this? Or lessen it Will it go away?? Should I add some fermented veggies or take a probiotic or something?! I really want to do the hack for weight loss and gut issues, but I cannot if it gives me vile farts all the time.
This is not a common complaint, but I have heard this before. Mostly from low carbers who have stopped eating potatoes. I hear many complain of this and i also had this problem. Eat a few slices of raw potato every day, to change your gut. I would clean out my colon first. If there is a dead animal up there ,it will come out. Gas and bloat can last a while, eat some greens along with potato for a couple of weeks, then , slowly drop the veggies down to just Taters, if that is your goal.
Tired, spaced out, hungry. That said, I have also been working out a lot…twice a day, 4 days a week. Would this still allow me to see fast results or does it somehow undermine the science of it all? Thanks and this site is really amazing! One of the variations discussed in the variation chapter is to add a source of lean protein in a meal on its own.
So, like oz of lean beef, chicken, or fish for a light lunch. Then a big potato dinner. Some say this works really well for those that are very active. I turned a friend of mine into a Potato-by-day hacker and she asked me if I knew anything about where to keep potatoes. I found this online: Instead of putting potatoes in the fridge, store them in a paper bag in a cool — not cold — place.
Best to store in a cool, dry place, like a garage, basement, or cellar. But, if none of these are available, just keep at room temperature away from heaters and windows. The bag they come in usually provides all the protection they need. Potatoes keep fine for weeks like this, just like in the grocery store.
I just started this plan today and baked 5 pounds of potatoes in the crock pot. However, they had been stored in the fridge for a couple weeks. Should I toss these out because of them possibly converting to sugar? High-reducing sugar concentrations result in undesirably darkened potato chips and fries. Some varieties recondition better from low temperatures than others. Thank you so much for the quick response, and on a Sunday! I threw away those potatoes and started with fresh ones, not stored in the fridge.
I just bought a potato ricer and it really changed the flavor of the potato by making it like little pieces of rice. I boiled the red potatoes and then put them through the potato ricer, added some chives and salt and it was delicious.
It is also a good idea to keep potatoes and onions separate. Apparently the each emit gasses that hurt each other. We now store pasta in that drawer. Now I keep them in separate ventilated canisters and they are just fine. The regular, non-organic potatoes are likely killed by a chemical that keeps them from sprouting.
The organic ones, like Tim says, sprout and eventually go soft. If they are firm, I just scrape the sprouts off. Hello Tim, Greetings from Pakistan! I am a 44 year old man. I binge when I am in stress and more food when I am depressed. Pre-diabetic, blood pressure, you name it. I will eat nothing but potatoes for two weeks and see how it goes. Just to motivate me, what kind of weight loss folks have seen in two weeks of doing all potato diet?
It should work perfectly…you are exactly the type that responds best…middle-age male with metabolic syndrome. Potatoes only, no butter or bits of foods…just potatoes. I bit of salt, pepper, or spice of preference. All kinds of ways to cook them… pick up a copy of the book to download or read to pass the time while losing weight. I would predict anything from 5 to 15 pounds. It will be a journey for sure!
Let us know how you do. Thanks for your reply. I just bought the kindle version from Amazon. I will read it through and I am really excited. I will keep you guys posted. I just started my 4th hack tonight. I was extremely hungry this afternoon, but all i wanted was an enormous plate of hash browns for dinner. I took that as a sign that my body was ready for another potato hack. Any thoughts on this Tim? Thanks for the feedback, Robin. But what I wanted to comment on is the HCG diet.
I would lose about lbs but I always gained it back no matter what I did, and quickly. It was very upsetting. I was beyond miserable on that diet and I suffered the whole time. I hit a stall after losing lbs on a paleo diet several years ago and my weight has fluctuated ever since. Ready to get off this merry go round and find what works for me once and for all. The best way to lose pounds with the potato hack is to faithfully do days a week, eating mindfully in between potato days, for a couple months.
Then use day hacks intermittently to keep the weight off. Hi Tim, thanks for the response! I figure I can do it weekly for months, then every so often to keep my weight in check. Absolutely brilliant if it works. I wish I had known about this sooner! One more thing I wanted to mention but forgot, which I think is amazing and important for anyone considering this hack.
I have always struggled with sugar and sugar cravings. I have been able to go long periods without it out of sheer will in the past but I struggled every day. Hi Tim, Does the rate of cooling matter? If I put them outside in C for a few minutes does that matter, or is there a RS formation issue if its too cold? So far so good. Feeling hungrier today so that means its working right? I know ketchup is ok but what about hot sauce? Hi Tim — I have been diagnosed with insulin resistance.
Would you still recommend using the potato hack for weight loss under this circumstance. Gina — First you should get a blood glucose monitor they are cheap: See on Amazon , and start checking your fasting blood glucose as well as seeing how you respond after meals.
Depending of the severity of your insulin resistance, the potato hack might be just fine, and in fact, might reduce your fasting and after-meal numbers compared to your present diet. Thanks for the quick response! My husband has blood sugar issues, so we have a monitor. Thanks for sharing all of this great information. I eat potatoes days and whatever I want the rest of week. Hard to say what causes lighthead and dizziness.
Dehydration, lack of salt? Maybe take it easy for a couple weeks and let your body catch up. So, I made a mistake on those numbers and the amount of time…I have lost 30 lbs, but 10 of those pounds were back in December. I have a dr apt Thursday. I take medication for high blood pressure, wondering if maybe my blood pressure has dropped due to the weight loss, which would account for the lightheaded and dizziness.
Especially if you could avoid snacks and your lunch was comprised of super-healthy foods, ie. This is close to what I do every day. But — some constipation issues, and my fasting glucose number was up there.
I skip breakfast and lunch is some kind of small healthy thing. I think the key might be that once the gut is in a good place, the body is more likely to reach for its optimal set point of weight, up or down as the case may be..
Weight gain is harder and takes longer than weight loss, as I know from my own experience and trying to fatten up a loved one or two. I think you may be correct about getting the gut to optimal levels first.
Brenda, are you familiar with the Ayurvedic system of the three doshas body types? They at least take into account that some people the vata type are just plain thin and tend to get thinner than they want to.
Can you use any type of potato or does it have to be a certain one? I tend to like the red potatoes myself. Mix it up with different varieties. The Potato Hack Chronicle Weight loss, gut health, and mental well-being using potato diets, resistant starch, fiber, and potato science! Weight Loss The potato hack can be used whether you need to lose pounds or 2 pounds.
Quick Fat Blaster; pounds This is almost too easy. Conclusion If you just need to lose a couple pounds, a lot of pounds, or want to keep weight off long-term, The Potato Hack may be just what you need.
See what others are saying: Soule72 June 4, at 4: Tim Steele June 4, at 5: Dan Dell'uomo February 18, at 2: Populations have lived on almost nothing but sweet potatoes and been perfectly healthy: Read all about it: Sara July 13, at Does it get better?
Sara July 13, at 2: Tim Steele August 5, at 6: Sorry, did not see this comment earlier! Did it get better? Yvonne July 25, at Elisabeth Lee August 5, at 5: Mike Callahan August 15, at 4: Noah Strawn August 17, at 2: Tim Steele August 17, at 3: The potato hack is very safe, and many tell me it works better than HCG to keep hunger away.
Anita August 22, at Tim Steele August 22, at Jeffhalmos August 23, at 4: Tim Steele August 23, at 4: Good luck to you all! Brittany August 25, at 6: Tim Steele August 25, at 6: Great blog you have…I hope to live in Hawaii one day.
Brittany August 25, at Cats also develop FAD, which is one of the major causes of feline miliary dermatitis. FAD is most prevalent in the summer, although in warm climates flea infestations may persist throughout the year.
In north temperate regions, the close association of pets and their fleas with human dwellings creates conditions that permit a year-round problem. Temperature extremes and low humidity tend to inhibit flea development. When feeding, fleas inject saliva that contains a variety of histamine-like compounds, enzymes, polypeptides, and amino acids that span a wide range of sizes 40—60 kD and induce Type I, Type IV, and basophil hypersensitivity. Flea-naive dogs exposed intermittently to flea bites develop either immediate 15 min or delayed 24—48 hr reactions, or both, and detectable levels of both circulating IgE and IgG antiflea antibodies.
Dogs exposed continuously to flea bites have low levels of these circulating antibodies and either do not develop skin reactions or develop them later and to a considerably reduced degree. This could indicate that immunologic tolerance may develop naturally in dogs continually exposed to flea bites.
Although the pathophysiology of FAD in cats is poorly understood, similar mechanisms may exist. Clinical signs associated with FAD are variable and depend on frequency of flea exposure, duration of disease, presence of secondary or other concurrent skin disease, degree of hypersensitivity, and effects of previous or current treatment.
Nonallergic animals may have few clinical signs other than occasional scratching due to annoyance of flea bites. Those that are allergic will typically have a dermatitis characterized by pruritus.
In dogs, the pruritus associated with FAD can be intense and may manifest over the entire body. Classic clinical signs are papulocrustous lesions distributed on the lower back, tailhead, and posterior and inner thighs. Dogs may be particularly sensitive in the flanks, caudal and medial thighs, ventral abdomen, lower back, neck, and ears.
Affected dogs are likely to be restless and uncomfortable, spending much time scratching, licking, rubbing, chewing, and even nibbling at the skin.
Hair may be stained brown from the licking and is often broken off. Common secondary lesions include areas of alopecia, erythema, hyperpigmented skin, scaling, papules, and broken papules covered with reddish brown crusts. The rump and tailhead areas are typically the first, most evident, areas affected. As FAD progresses and becomes chronic, the areas become alopecic, lichenified, and hyperpigmented, and the dog develops secondary bacterial and yeast infections.
In extremely hypersensitive dogs, extensive areas of alopecia, erythema, and self-trauma are evident. Traumatic moist dermatitis hot spots can also occur. As the disease becomes chronic, generalized alopecia, severe seborrhea, hyperkeratosis, and hyperpigmentation may develop.
In cats, clinical signs vary from minimal to severe, depending on the degree of sensitivity. The primary dermatitis is a papule, which often becomes crusted. This miliary dermatitis is typically found on the back, neck, and face. The miliary lesions are not actual flea bites but a manifestation of a systemic allergic reaction that leads to generalized pruritus and an eczematous rash.
Pruritus may be severe, evidenced by repeated licking, scratching, and chewing. A number of factors must be considered in the diagnosis of FAD, including history, clinical signs, presence of fleas or flea excrement, results of intradermal testing, and exclusion of other causes of dermatologic disease. Most cases are seen in the late summer, corresponding to the peak of flea populations. In these cases, history can be highly suggestive. Age of onset is also important, because FAD does not ordinarily occur before 1 yr of age.
Usually, diagnosis is made by visual observation of fleas on the infested pet. Demonstration to the owner of the presence of fleas or flea excrement is helpful. Slowly parting the hair against the normal lay often reveals flea excrement or the rapidly moving fleas. Flea excrement is reddish black, cylindrical, and pellet- or comma-shaped. Placed in water or on a damp paper towel and crushed, the excrement dissolves, producing a reddish brown color.
Extremely hypersensitive animals are likely to be virtually free of fleas because of excessive self-grooming.